Paul Scholes has suggested that Manchester United's Premier League title bid hinges on the likes of Arsenal and Manchester City slipping up.
Louis van Gaal's side laboured to a 2-1 win at Watford on Saturday as Troy Deeney's stoppage-time own goal briefly lifted the Red Devils to the summit.
Leicester City later usurped them on a day which also saw the Gunners and City suffer defeats to sit one point behind Van Gaal and co.
"Are they good enough to go on and win the league? I'm not 100 per cent convinced, I think Manchester City and Arsenal would have to struggle with injuries and form," he told BT Sport.
"That says everything about them and is typical of the way Manchester United have played this season."
United face the Foxes next Saturday in a top-of-the-table clash at the King Power Stadium.