A spirited Brighton side fought valiantly but in the end Mourinho's squad came away with three points at Old Trafford. Meanwhile, West Brom managed to come away with a precious point against Tottenham, while a late goal by Mamadou Sakho against Stoke City secured a victory for Crystal Palace.
A spirited Brighton side fought valiantly but in the end Mourinho's squad came away with three points at Old Trafford as Manchester United won 1-0. Meanwhile, West Brom managed to come away with a precious point against Tottenham as the score ended 1-1 at Wembley, while a late goal by Mamadou Sakho against Stoke City secured a 2-1 victory for Crystal Palace.
Elsewhere, Marco Silva's reputation keeps growing as Watford routed Newcastle 3-0 and a controversial call ensured a 0-0 result between Swansea and Bournemouth.
Read up on all the action below.
An unfortunate Lewis Dunk own goal meant Manchester United were able to overcome a spirited Brighton side to win 1-0 at Old Trafford.
Jose Mourinho named an unchanged side to that who beat Newcastle 4-1 in their last Premier League outing, whilst Chris Houghton made one change to his side that drew 2-2 at home to Stoke - Jose Izquierdo losing his place to Solly March. Manchester United were coming off the back of a 1-0 defeat to FC Basel in the Champions League midweek, where as Brighton hadn't lost any of their last five games.
The first chance of the game fell on two minutes when Romelu Lukaku played a neat one-two pass with Anthony Martial, finding space to shoot on the edge of the area, however he was unable to direct his shot on target. It was then Brighton who began to pressure the home side, getting two shots on target but failed to really test David de Gea.
The ensuing half an hour followed a similar pattern, with Manchester United dominating possession but Brighton stayed strong defensively and looked threatening on the counter attack. The best chance of the half fell just before the break when Lukaku's close range header was stopped by Ryan before he then blocked Paul Pogba's rebound to complete a brilliant double save.
The sides went into the break level, and the start to the second half saw a similar pattern to that shown in the first half. United were left frustrated by the stern Brighton defence who were dealing with everything that was thrown at them, with the visitors also looking threatening going forward.
With Brighton looking comfortable at the back, Mourinho brought on Zlatan Ibrahimovic just past the hour mark to try and break down the opposing defence, and just five minutes later United went in front.
Marcus Rashford's corner was cleared only as far as Ashley Young on the edge of the area, who's ensuing shot took a wicked deflection off Lewis Dunk and looped over Ryan into the back of the net to put the hosts in front.
Despite going behind, Brighton still looked threatening on the counter. Dunk brought the ball out from defence and found himself on the edge of the 18-yard box with a sight at goal, unfortunately he got his feet tangled and couldn't find a shot on target, but Brighton were responding well to going behind.
A matter of minutes later, Anthony Knockaert fizzed a very teasing ball across the face of goal, however there weren't any Brighton players to turn the ball home. The visitors then had a near identical chance not long after when Bruno got forward from right-back and put a very inviting ball across the face of goal, but again no Brighton players could get on the end of the cross.
The game began to open up, with the away side continuing to put the pressure on the United defence. With five minutes remaining, Shane Duffy should've tested De Gea with a header from an inviting free kick, however he couldn't direct his header on target.
Ibrahimovic then had a chance to seal the points for United, playing a neat one-two pass with Pogba before lashing his shot wide of the Brighton goal. Despite Brighton's spirited performance, United were able to see out the game and maintained their 100% home record in the Premier League this season.
The win now means United have cut the gap on league leaders Manchester City to five points - who travel to Huddersfield Town on Sunday - whilst Brighton drop to ninth in the league and lose their first game in five matches.
West Bromwich Albion held Tottenham Hotspur to a 1-1 Premier League draw at Wembley Stadium on Saturday afternoon.
Salomón Rondón's carefully caressed effort gave the visitors a shock lead within five minutes, stunning the hosts with their incisive breakaway. Spurs kept the pressure up, and finally got their breakthrough in the second half as Harry Kane guided home the equaliser.
West Bromwich Albion stunned Spurs in the fourth minute, opening the scoring to the delight of the travelling support. Jake Livermore dispossessed Dele Alli on the half-way line before feeding a through ball to Rondón. The Venezuelan international then burst passed Davinson Sánchez and saw his delicately placed shot creep passed a flat-floored Hugo Lloris.
The visitors prepared for an onslaught, packing their midfield and defensive lines to thwart Mauricio Pochettino's side's short passing game. Spurs kept the possession, but failed make inroads into the Baggies' stubborn defence. Harry Kane saw a firmly struck shot edge just wide of the post in the 27th minute, as his side were restricted to long-distance pot-shots at goal.
Son Heung-min came close to scoring an equaliser in the 32nd minute, cutting inside and firing a dipping 25-yard effort at Ben Foster, who tipped the ball wide of the post. The home side began to grow in confidence, and their frustrated fans began to provide them increased vocal support.
In the 41st minute Eric Dier came agonising close to helping his side draw level. Kieran Trippier whipped a devilish corner into the penalty area, and Dier rose like a salmon in the air but his header was comfortably caught by Foster. In the 45th minute Son burst down the wing, firing a scross across the goalmouth which a stretching Kane couldn't quite reach.
Spurs game bursting out the traps in the second half, as they looked to overturn the visitors narrow lead. However, it was the Baggies who had the best first chance of the second half in the 56th minute, as Matt Phillips drove inside and saw his curling low shot creep wide of the Lloris' far post.
Alli came agonisingly close to pulling it level in the 69th minute, but couldn't quite get on the end of Kieran Trippier's deflected shot. Spurs finally equalised in the 75th minute, as Kane latched onto Dele Alli's smart pass to clinically stab the ball through Foster's legs from inside the six yard box.
Spurs went for the jugular, pouring forward with rapid attacking play. West Brom were on the ropes, desperately scrambling to hold back the tidal wave of the home side's attacking play. Kane came close to bagging the winner in the 83rd minute, and saw his close-range header somehow go over the bar from five yards out.
The pressure was relentless, as Spurs marauded forwards time and time again. The Baggies held strong, and claimed a well-deserved and precious point. Pochettino will have been hugely frustrated with his side's inability to break down the West From defence, while Baggies manager Gary Megson must be applauded for his side's steely discipline when under pressure.
Saturday afternoon saw Crystal Palace take on Stoke City at Selhurst Park, with the Potters looking the better side as they had two wins in their last six games.
Though Palace got their first win of the season against Chelsea, Roy Hodgson still needs to establish himself at the South London club as they still struggle to perform after sacking Frank de Boer.
The opening minutes of the game looked solid for the Eagles as they were pushing the ball up front trying to create chances with Yohan Cabaye continually trying to cross into Stoke's box.
It wasn't until the 16th minute that the hosts got a solid chance as Wilfried Zaha whizzed past two defenders trying to get the ball to Ruben Loftus-Cheek, only for Erik Pieters to block the shot afterwards.
Another attempt to break the lock came just before the half-hour mark as Luka Milivojevic tried to force a shot from 25-yards out, but it went wide from the away goal.
Xherdan Shaqiri looked liked the talisman of the Stoke side trying to get an opener but the Swiss winger failed to convert any of his chances in the first half.
The noise grew amongst home fans as Zaha was fouled by Kevin Wimmer near the end of the first 45, believing that it was a bookable offense as the Ivorian was in pain after Wimmer trod on his ankle.
The first half ended goalless as the Eagles struggle to find a breakthrough in the Premier League stuck at the bottom of the table.
In the second half, Palace looked to increase the pressure on the Potters by bringing on Christian Benteke.
Seven minutes in, he had his first attempt on goal with a shot going wide from eight yards out after a ball from Cabaye.
The visitors finally made a breakthrough in the 53rd minutes as Shaqiri made an impressive solo run all the way from the halfway line to drive the ball from the edge of the box and into the net.
However, Stoke fans' celebration ended quickly as only three minutes later, Chelsea youngster Loftus-Cheek got the goal that would bring the game back on level terms.
A low cross from Andros Townsend dazzled the Potters, as the midfielder calmly slotted the ball into the net from close range.
The next 20 minutes saw both sides apply immense pressure to each other as Benteke went for another attempt on goal while Jese Rodriguez tried to respond immediately after.
As the game went on, players from both sides seemed to get tired as they were starting to make mistakes on the ball.
Home fans were given a fright in the closing minutes of match as Ryan Shawcross was a yard away from goal and messed up a cross from Shaqiri.
With a final attempt on goal, Palace went all out as Stoke tried to clear the ball. Cabaye's attempt to shoot allowed Mamadou Sakho to pounce on the rebound and the Frenchman found the back of the net with a tap in.
The match ended with the roar of Eagles as Crystal Palace win their second game of the season.
Newcastle put in one of their worst performances of the season as Watford convincingly beat them 3-0 with a fantastic display of counter-attacking football.
Watford captain Troy Deeney sat out the last game of his three match suspension, as did Newcastle's Issac Hayden who received his fifth booking against Manchester United.
Mikel Merino returned from a back injury and was expected to replace Hayden but could only make the Newcastle bench, with Jacob Murphy keeping his place in the starting eleven after impressing at Old Trafford.
It took eleven minutes for the first big chance of the game - Murphy, who was Newcastle's best player, played it to Matt Ritchie on the right-hand side of the penalty area but his curled shot could only find the side netting.
Watford then replied with an electric counter-attack which resulted in Rob Elliot having to turn Richarlison's shot round the his left hand post with a fantastic save.
The Hornets started to grow into the game and it wasn't long until they opened the scoring after some awful Newcastle defending - Marvin Zeegelaar was given far too much time down the left to pick out a low driven cross for the unmarked Will Hughes to sweep home from the penalty spot.
Newcastle did not learn from their mistakes and just two minutes later, Zeegelaar was given the freedom of St James Park to pick out Abdoulaye Doucoure but the Frenchman could only flick wide from six yards out.
The Magpies responded by creating chances of their own - the best of which came when Joselu rolled the ball across Heurelho Gomes' goal in the 36th minute; the final ball just seemed to be lacking for the Toon.
However, Newcastle were fishing the ball out of their own net once again on the stroke of half-time and it came down Watford's left once again - that man Zeegelaar providing a dangerous cross that DeAndre Yedlin could only turn past his own keeper.
A dire first half from Newcastle would have been met with stern words from their manager Rafa Benitez in the changing rooms, but there didn't seem to be any improvement from his players as Andre Gray spurned a glorious chance and then a few minutes later saw a shot blocked by Yedlin.
Gray finally got his goal just after the hour mark when Richarlison did magnificently do keep the ball in play down the left hand side and superbly crossed for the striker too tap in from close range.
Rafa's persistence with the struggling Spaniard Joselu was further questioned in the 66th minute when Murphy played him through beautifully but instead of taking a touch and picking his spot, he decided to slide and fling a leg at it, resulting in the ball calmly rolling into Gomes' hands.
Gray really should have had a hat-trick on the day as he found himself one on one with Elliot in the 82nd minute but his shot lacked any real conviction and trickled into the keeper's palms.
Toon fans' hopes and prayers were answered when Aleksandar Mitrovic replaced Joselu and the Serbian almost got a consolation in the 86th minute but for some heroic defending from Christian Kabasele to block the shot.
That was Newcastle's fourth loss on the trot, with Tuesday's game at manager-less West Brom now looking like a must-win - whilst Watford maintain their charge up the table despite the ongoing speculation surrounding their marvelous manager Marco Silva.
Swansea's winless run against Bournemouth has stretched to six matches after they were held to a controversial 0-0 draw at the Liberty Stadium.
Wilfried Bony's goal in the final throes of the first half was ruled out in arguable fashion after Jordan Ayew was adjudged to have fouled Nathan Ake, and prevented Paul Clement's Swans from chalking up a rare three points.
Eddie Howe's visitors held off extensive second half pressure from the hosts, but did little to truly deserve a third successive league victory.
Bournemouth had the better of the game's early opening, with Marc Pugh, Andrew Surman and Nathan Ake drawing saves of varying quality from Lukasz Fabianski.
Swansea's final ball was letting them down whenever they ventured forward - a point hammered home by Renato Sanches' wasteful cross on a rare counter attack.
Two chances in quick succession, both set up by Tom Carroll, saw Martin Olsson and Sanches fire wide as the hosts tried to wrest control of proceedings from Bournemouth, while Fabianski was alert to Joshua King's low drive.
Swansea were apopleptic on the stroke of half-time after Bony's curling shot was ruled out, but replays suggested that Ayew was merely stronger than Ake and the goal arguably should have stood.
Adam Smith and Sanches traded off-target shots in the opening minutes of the second 45, and it was the latter of those efforts that seemingly inspired Swansea into life as they finally begun to boss proceedings.
The hosts were failing to make the most of their dominance though and they were almost made to pay as Fabianski's diving save prevented Jordon Ibe from breaking the deadlock.
Handbags between Ibe and Ki Sung-yeung added a bit of bite into a game that had been simmering for a while, and Roque Mesa required treatment on a wound after being caught by an elbow from Joshua King.
Leroy Fer inexplicably fired wide from his own rebound after Asmir Begovic had spilled his initial effort following a powerful run from deep before Swansea fans vented their fury as Tammy Abraham fell under Smith's challenge on the 18-yard line with no penalty given.
Charlie Daniels dragged a shot just wide of the upright in time added on, but both sides had to settle for a share of the spoils in the end.