Man United legend Roy Keane has admitted it will frustrate him Man City are able to win a historic Treble this season.
Pep Guardiola's side are closing in on the impressive accomplishment after beating Sheffield United 3-0 in the FA Cup semi-final on Saturday.
With the Premier League title race heating up and City scheduled to face Real Madrid in the Champions League semi-final, talk of a Treble has been rife recently.
And, after the match, United legend Keane revealed it would be difficult to see his side's rivals reach the achievement but warned that there is a long way to go.