Mourinho’s Manchester United side face Arsenal in the Premier League tonight.
United have competed in the Champions League this term, with Arsenal resigned to fighting it out in the Europa League.
Previewing Wednesday’s game, Mourinho suggested the Gunners will be fresher because they play in European football’s secondary club competition.
“It’s a very difficult match for us,” Mourinho said.
“We play against a good team in a good moment with a good run of results [but] without the accumulation of matches because they play Europa.
“When you play Europa League you normally play with second choices and you can give a good rest to your [first team] players compared to those in the Champions League, where we have to play in the maximum of our potential.
“It’s an accumulation of matches and you arrive in December where many teams pay the price for that.
“When you play Europa – I have done that – it’s not the motivation for the club but it’s good to develop the team and to have people fresh.”
Yet it appears as though Mourinho has changed his position from two years ago, when he was much more critical of the Europa League.
Back in the 2016/17 season, Mourinho led Manchester United to Europa League glory and a passage back into the Champions League.
But the Portuguese boss was critical of the Thursday-Sunday routine of playing matches.
“It’s more difficult, yes [to win the Premier League when you are playing in the Europa League],” Jose Mourinho said back in 2016.
“It would be better if we had the privilege of playing on a Monday after a Thursday game to have one day [recovery] but we didn’t get that privilege.
“In fact, the gift we have is to play Liverpool on the Monday before, not the Monday after. So we play Liverpool on the Monday, Fenerbahce on the Thursday and Chelsea on the Sunday. So we know that we are not going to have any kind of support on that.
“We are not going to make a drama out of it.”
United’s form in matches immediately after Champions League games this season reads W2 D2 L1.
It has been enough to secure their safe passage into the knockout stage of this season’s competition.
Their form after the six Europa League group games in the 2016/17 season – during which Mourinho was in charge – read W2 D2 L2.
As for Arsenal, their record in post-Europa League games this season reads W3 D2 L0.
The Gunners are already through to the last-32 stage of the competition with one game remaining.