The Gunners boss has been impressed with United's summer signing Anthony Martial
The 19-year old arrived for £36 million this summer - according to BBC Sport – in a move which raised eyebrows, but has since silenced doubters with a storming start to life in England.
The former Monaco man has bagged four goals in five appearances for United, and Wenger admits his form has come as a shock.
"He needs to maintain that and it will be very difficult for him.
"You have to have some understanding if he starts to score less, because he has already set the expectation at a very high level.
"But I am not surprised he does well because he is a very talented player."
Wenger previously claimed he opted against signing Martial – as reported by the Daily Express - because he viewed him as a winger as opposed to a number 9 – the position in which he has been excelling for Louis van Gaal’s team.
The talented forward has played a key role in United’s rise to the summit of the Premier League standings, and confidence is slowly growing around Old Trafford regarding their title prospects.
The Red Devils were considered to be outsiders before the season kicked off, but Chelsea’s erratic form and Manchester City’s recent dip has brought about a new wave of optimism on the red half of Manchester.