The Red Devils will take on fourth-placed Tottenham Hotspur in the FA Cup semi-final at Wembley on Saturday evening.
Manchester United are six points ahead of Spurs in the Premier League table but are 13 points adrift of English champions Manchester City.
Jose Mourinho’s side lost 2-1 to La Liga giants Sevilla in the Champions League round of 16 last month, while Championship side Bristol City beat Manchester United in the League Cup semi-finals.
The Red Devils could end the season without silverware unless Mourinho is able to mastermind a way past Spurs in the FA Cup semi-final.
Tottenham were 2-0 winners against Manchester United back in February following Christian Eriksen’s second-minute strike before Chris Smalling netted an own goal at Wembley.
Former Arsenal star Merson believes Manchester United’s entire season hinges on whether the Red Devils manage to beat Spurs at Wembley this weekend.
“A lot depends on this game,” Merson told Sky Sports. “Watch this space for either team.
“If I’m a United fan, if they win the FA Cup at least I’d sit there and go, ‘You know what, we won the FA Cup, come second in the league, let’s see next season’. If they lose this, you’ll be wondering, ‘Where are we going from here?’. It was a shocking result against West Brom, and it all comes down to this game.”
Manchester United won the FA Cup in Louis van Gaal’s final season in charge following a 2-1 extra-time win against Crystal Palace.
The Red Devils won the Europa League and the League Cup in Mourinho’s first campaign in charge at Old Trafford.
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