The Red Devils ended a run of two successive defeats earlier this month thanks to a 3-0 win against Shrewsbury Town in the FA Cup on Monday followed by Thursday night’s 5-1 Europa League victory over FC Midtjylland.
Arsenal, meanwhile, are on the brink of exit from Europe after a disapointing 2-0 loss to Barcelona in the first leg of their Champions League last-16 tie.
Former Scotland international Gray believes Arsene Wenger’s side will have too much quality for the 20-time English champions.
“The way Man United are at the moment, any win is good,” Gray told Paddy Power.
“All this talk about turning a corner though is confusing me, they’ve only beaten Shrewsbury and Midtjylland. Well get a better idea this weekend. Arsenal are a better barometer to see if they’ve turned a corner.
“I like the look of the Gunners. United have been hit by injuries badly, and Arsenal got an important win over Leicester last weekend.
“Yes, they did lose to Barcelona mid week, and were a bit flat in doing so, but I think they’ll go to Old Trafford and break a long hoodoo in the Theatre of Dreams.”
Arsenal are in third place in the Premier League table and two points behind leaders Leicester City.
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The Red Devils are in fifth place and six points behind bitter rivals Manchester City, who occupy the final Champions League qualifying spot.
The 20-time English champions are being heavily linked with Jose Mourinho.
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