MANCHESTER, England -- Jose Mourinho insisted the 3-1 derby defeat to Manchester City will not change his mind that Manchester United are getting better.
United were beaten at the Etihad Stadium to leave Mourinho's team eighth in the Premier League table, 12 points off the top and seven points adrift of the top four.
However, the Portuguese coach said afterwards they had not delivered a "bad" performance and insisted United are improving.
"We are not going to be affected by this," Mourinho told a news conference.
"I am just sorry we don't play the next match soon and have to wait 13 days for that, but we are improving, we are together and go together until the end."
Mourinho was forced to leave out Paul Pogba after the Frenchman suffered an injury during the midweek victory over Juventus.
Marouane Fellaini was drafted in to take his place and Mourinho believes the result might have been different had the Belgian been available from the bench with the score at 2-1 before Ilkay Gundogan wrapped up the points with City's late third goal.
"I can just imagine when the result was 2-1 to bring a fresh Fellaini to the pitch," said Mourinho.
"I think they would be in big, big trouble. But when the result was 2-1 and we had that final push, Fellaini was doing an incredible effort to stay on the pitch, not fresh at all, risking his injury and condition and to give everything for the team.
"For different reasons we missed Paul but that doesn't mean with Paul we win the game so it is not an excuse."
United have now conceded 21 goals in their first 12 league games for the first time since 1966 and are the only team in the top half of the table with a negative goal difference.
Mourinho made signing a new centre-back a priority in the summer but couldn't get one over the line before the deadline.
However, asked afterwards whether the goals against column was proof he was right to pursue a defender in the transfer window, he refused the chance to make a point to his board.
"I don't think today was the game to touch on that point," he said.
"I think Victor [Lindelof] and Chris [Smalling] had a positive performance.
"A kid [Luke Shaw] that made a mistake for the first goal is playing so, so, so, so well and last season he was playing one match every three months and in this moment he is playing every game for 90 minutes.
"When I speak about physical fatigue, mental fatigue that leads to mistakes during the game that's what I mean.
"I consider the performance of my team a performance with mistakes. It is different than a bad performance. One thing is a bad performance, another thing is a performance with mistakes.
"We made mistakes and were punished for these mistakes, but the performance, the mentality, the togetherness, the fight until the end was something we are building and we are not going to lose that because of a defeat."