The Gunners head to Old Trafford needing a victory to close the gap to leaders Leicester back down to two points after the Foxes’ 1-0 win over Norwich on Saturday.
For the first time in Premier League history, Arsenal are the favourites to beat the Red Devils at their home ground.
The north London side head into the game looking to bounce back from their disappointing 2-0 loss to Barcelona in the Champions League in midweek.
And former Arsenal striker Henry feels that the Gunners can take plenty of confidence from United’s recent stuttering form heading into Sunday’s showdown.
Writing in his column for the Sun, Henry said: “Arsenal face Manchester United today knowing there has never been a better time to go to Old Trafford.
“United are wounded, both physically and mentally, with so many players out injured.
“Not so long ago, United versus Arsenal was the biggest game of the Premier League season, first against second in a virtual title decider.
“Today’s game is still massive but for all the wrong reasons. United need to win so boss Louis van Gaal can hang on to his job for another week. Arsenal must bounce back from another setback in Europe.
“For the Gunners, it is the start of a run of six away matches which will decide whether they are going to win their first title in 12 years.
“After Old Trafford they visit Spurs, Everton, West Ham, Sunderland and Manchester City — and they need to take at least 12 points.
“But, unlike United, at least they are still in the title race.”
Arsenal are aiming to win their first Premier League title since Henry was still at the club back in the 2003-04 season.
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