Twitter Heavily Trolls Manchester United After Sanchez Benching & Salah's Liverpool Magic

After Mohamed Salah's four-goal haul in Liverpool's crushing 5-0 win over Watford, all eyes were on Manchester United to produce a comfortable victory and progress to the FA Cup semis against Brighton. 

With the Red Devils exiting Europe in midweek, falling to a shock home defeat by Sevilla, Jose Mourinho needed a performance to help growing discontent at Old Trafford.

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Instead, he had to look at a typically disjointed showing from the Manchester club, with a Romelu Lukaku goal putting his charges ahead before the break. 

Brighton had several chances to equalise, with the Seagulls causing nerves all around the Theatre of Dreams before Nemanja Matic put the game beyond doubt in the final ten minutes. 

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Mourinho praised the Serbian after the game but ripped into his team-mates, citing a lack of desire amongst some players.

Twitter was quick to react to the two contrasting results, with the Portuguese panned for his judgement on Salah after the Liverpool forward netted four times against Watford. 

The two worked together in Mourinho's second spell at Chelsea, with the then-manager shipping him off to Fiorentina on loan a year into his Stamford Bridge career, making only 19 appearances for the west London club.

With Kevin De Bruyne, Juan Mata and Romelu Lukaku other ex-Blues deemed not good enough for his team, with the latter two currently in his squad and the former arguably the best player in the Premier League, questions have been raised about the judgement of the United boss.

Mourinho launched an impassioned 12-minute defence of his United reign prior to Saturday's game against Brighton, listing the records of the previous men in the hot seat after Sir Alex Ferguson's retirement and stressing the size of the rebuilding job he was left from Louis van Gaal, despite spending upwards of £300m since his arrival.

With the recent publicised arrival from Alexis Sanchez in January seemingly breathing new life into the Red Devils' title charge, the Chilean has not set the world alight in the early days of his Old Trafford career, being virtually invisible in Tuesday's Champions League exit.

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Arsenal fans have been delighted with this, what with his replacement Henrikh Mhkitaryan showing signs of fitting in seamlessly with Mesut Ozil and the rest of the Gunners frontline.

After the Portuguese coach dropped Sanchez for the cup quarter-final, Arsenal fans on Twitter wasted no time in having a dig at their rivals.

ArsenalFanTV regular Moh Haider mocked the elaborate signing video United produced, depicting Sanchez playing a club anthem on the piano.

With the Gunners still in Europe, albeit in the Europa League, the north Londoners have much to be positive about despite the recent struggles and questions over Arsene Wenger's future refusing to go away.

At Old Trafford, however, with the Manchester club so far behind their city rivals in the league, an FA Cup triumph would be the only tonic to an underwhelming season.