Chelsea beat West Ham 1-0 at Stamford Bridge on Sunday afternoon, ending their poor home form in recent matches.
The first half was relatively quiet between the two sides as Thomas Tuchel's Blues failed to put too much of note together in the final third.
As the Blues came out for the second half, they quickly began to put more together in the final third, although still struggled to break the deadlock.
After a long 90 minutes of football, substitute Christian Pulisic managed to put his side ahead in the last minute of the game, claiming all three points for the Blues.
Chelsea were unlucky in the warm up before Sunday's game, as they announced Andreas Christensen would miss the game due to stomach cramp.
The first 10-15 minutes didn't see too much action between the two sides, other than Said Benrahma stand on Cesar Azpilicueta's foot, splitting his boot and forcing him to swap.
Benrahma then went on to grab his side's first shot on goal in the 17th minute but Edouard Mendy had it all under control.
Trevoh Chalobah got the ball caught up in his feet a minute later but he was able to make up for his mistake by re-gaining possession swiftly after.
Chelsea have made a number of defensive mistakes in recent weeks, which has seen them lose their last three consecutive home games.
The Blues made several attacks throughout the first half through Timo Werner, Mason Mount and Kai Havertz but they seemed a little slow and indecisive in the final third.
N'Golo Kante was forced to help out a number of times to add some creativity but Thomas Tuchel's boys struggled to put too much together.
Every attack Tuchel's side put together was swiftly cut out by West Ham's rigid defending in numbers.
David Moyes' game plan seemed to be to save the likes of Declan Rice and Jarrod Bowen ahead of their European night on Thursday.
Instead, the east London side held the lines, stopping the Blues from creating much, and tried to break when they could on the counter-attack.
Neither side made any changes as the two sides re-emerged for the second 45 minutes.
Timo Werner had Chelsea's first proper opportunity of the second half, 52 minutes in as he ball fell to him inside the 18-yard box but the German's shot was blocked by Craig Dawson.
The next few minutes saw the home side keep the tempo high and apply plenty of pressure on the Irons.
A counter attack, not long after, saw Andriy Yarmolenko find Tomas Soucek who had West Ham's best opportunity of the game so far, but Thiago Silva managed to block his shot.
Trevoh Chalobah rifled a shot at Lukasz Fabianski from 30-or-so yards out just before the hour mark, but the Hammers' goalkeeper had it covered.
62 minutes into the game and Mark Noble made way for former Blues-prodigy Declan Rice.
After recently turning down his third contract offer, according to reports, the 23-year-old undoubtedly looked at the remaining half an hour as his perfect audition for a potential future move to Chelsea.
With neither team able to make a breakthrough, Thiago Silva decided to take it upon himself in the 68th minute, dribbling through to the Hammers' penalty area from the half way line.
But his shot was rifled straight into the back of an offside Timo Werner and the chance eventually amounted to nothing.
A minute later and Mendy made two crucial saves as Yarmolenko very nearly put his side ahead.
Less than 30 seconds later and both Mount and Werner were inches away from making it 1-0 Chelsea but expert defending from Dawson disallowed it.
74 minutes in and Timo Werner was desperately close to scoring, as the ball fell to him on the volley from eight yards out. Again, Fabianski was on hand to deal with the trouble.
A minute later saw Havertz, Werner and Loftus-Cheek all make way for the trio of Romelu Lukaku, Hakim Ziyech and Christian Pulisic.
With less than 10 minutes remaining in the clash, Craig Dawson, who had played an excellent game in West Ham's defence, brought down Romelu Lukaku inside the away side's box, conceding a penalty.
After a quick VAR decision, Dawson was shown a red card for denying Lukaku of a clear goalscoring opportunity.
However, in a huge let off for West Ham, Jorginho stepped up to take the penalty and sent it straight into the gloves of Fabianski.
Much to the away side's disappointment however, a swift low cross from Marcos Alonso saw Christian Pulisic finally find the back of the Irons net in the 90th minute to claim a late win for the Blues.