The Red Devils suffered a surprise 1-0 loss to West Bromwich Albion at Old Trafford following Jay Rodriguez’s 73rd-minute winner.
Manchester United’s defeat handed their bitter title rivals Manchester City their first Premier League crown under Pep Guardiola.
The 20-time English champions are in second place in the Premier League table but a mere point ahead of Liverpool FC.
However, Jose Mourinho’s men can move four points clear of the Champions League semi-finalists if Manchester United beat Bournemouth.
The Red Devils can still finish the season with some silverware if Manchester United beat Tottenham Hotspur in the FA Cup semi-finals to reach the Wembley showpiece.
Former Arsenal midfielder Merson believes Manchester United will make amends for their shock loss to West Brom with a slender victory over Bournemouth at the Vitality Stadium mid-week.
Merson told Sky Sports: “I can see Man Utd winning here, but I’ve never seen anything like their performance on Sunday against West Brom at the highest level. It was like ‘We’ll turn up and wipe the floor of these.’
He added: “Bournemouth are safe, and we underestimate them. Their ground has 12,000! We take it for granted when they stay up, and I don’t think they get the credit they deserve.”
Manchester United signed Chile international Alexis Sanchez in a swap deal from Arsenal in the January transfer window.
The Red Devils lost 2-1 to Spanish outfit Sevilla in the Champions League round of 16 last month.
Mourinho was appointed as Louis van Gaal’s successor in May 2016.
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