Marouane Fellaini has insisted Manchester United did their best in their 3-1 derby loss at Manchester City.
Jose Mourinho's men were showing some form going into the Manchester derby at the Etihad and were hoping to close the gap on the Citizens in the Premier League standings.
But it took just 12 minutes for the Red Devils to fall behind to their rivals when David Silva struck in the 12th minute.
Matters got worse for Manchester United three minutes into the second half when Sergio Aguero doubled the hosts' advantage, however an Anthony Martial penalty gave the Red Devils hope ten minutes later.
Manchester City were comfortable though and produced a stunning 44-pass move with four minutes left, finished off by Ilkay Gundogan, to kill off any thoughts of a Manchester United comeback.
Fellaini insists Manchester United had a tough week and gave all they could.
"It was a derby game, both teams want to win it but it was a tough game. High intensity", Fellaini said to the BBC's Match of the Day.
"We had a tough week with three games away, we competed, tried our best.
"It is frustrating for us."
Manchester United are now 12 points off league leaders Manchester City and ten off second placed Liverpool.
