The Red Devils have managed to remain unbeaten in their last three Premier League games after losing three of their opening seven top-flight games.
Manchester United came unstuck at Brighton and Hove Albion and West Ham United on the road to raise questions about their defence in away fixtures.
Tottenham Hotspur are the only Premier League team to win at Old Trafford this season following a 3-0 victory over Manchester United in August.
Mourinho’s side came from behind to secure a 3-2 win over Newcastle United at Theatre of Dreams last month before a 2-2 draw with title rivals Chelsea FC.
Anthony Martial produced a dominant performance to help Manchester United secure a 2-1 victory over Everton at Old Trafford last weekend.
However, Bournemouth will provide a stern test on the south coast this weekend given the Cherries’ incredible start to their fourth season in the Premier League.
The Cherries have managed to keep three successive clean sheets to go unbeaten in their last four games and hoist themselves up to sixth place in the table.
Former Arsenal midfielder Merson believes Bournemouth will extend that run to five games this weekend when Eddie Howe’s men host Manchester United at the Vitality Stadium.
“This is a bit of a level game, isn’t it?” Merson told Sky Sports. “Over the years you’d say these types of games are a walk in the park for Manchester United, but this is a hard game now.
“It’s a hard one to call, too. I went with Manchester United last week 2-1 against Everton because they’re Manchester United. It’s very hard to go against them. But I’m going for a draw here, and it’s a massive compliment to Bournemouth. That’s how far they’ve come, and also where Manchester United have gone too.
“United are sometimes better away, but Bournemouth will have a right go at them, and United are all over the place at the back.”
Bournemouth were 2-1 winners against Manchester United in their first-ever Premier League meeting in December 2015 when Louis van Gaal was still in charge of the Red Devils.
However, the Cherries haven’t beaten the Red Devils in their next five meetings, losing on four occasions.
Manchester United’s defence will have to be wary of Callum Wilson’s impressive form given the powerful striker has scored five times and has made four assists in 10 outings in the league this season.
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