The pacy winger was snapped during practice ahead of this weekend's Premier League fixture, despite Wenger telling reporters he has picked up another injury and will miss the game against United.
The Gunners boss's press conference, however, came before Arsenal's training session. So could Walcott actually be fit to play United?
There is perhaps no need to jump to any conclusions as, tellingly, Walcott cannot be seen in action, simply on the training field and carrying a bib. But the fact that the 25-year-old was out at London Colney at all will at least reassure fans that his newest injury scare should not be a long-term one.
Costa Rica forward Campbell's future has been the subject of heavy speculation this term, with the 22-year-old barely featuring in Arsene Wenger's first-team plans so far this season.
Puzzlingly, though, Arsenal do seem to want to keep Campbell at the Emirates Stadium. They just don't seem too keen on playing him...