"We've found a certain balance in the team", he added.
United have left Antonio Valencia back in Manchester as they didn't want to risk his troublesome knee on the artificial surface but Luke Shaw is back in contention after missing the Watford game due to concussion.
"We decided not to bring Antonio because his knee is not a knee that needs an artificial pitch at all", Mourinho told a news conference.
"I don't want to use that, especially before the match, as a possible excuse for a not good performance", he continued.
With a reference to Switzerland's greatest sportsman, 20-times Grand Slam victor Roger Federer, Mourinho urged his team to just get on with it. "We'll have to do it".
Mourinho has changed his routine ahead of United's Champions League opener.
Mourinho does not need to be reminded of the potential pitfalls of a visit to Switzerland, however.
Manchester United forward Romelu Lukaku has taken Marcus Rashford under his wing and is spending more than half an hour after every training session on attacking drills with the 20-year-old, Metro.co.uk understands.
Jose Mourinho's last European campaign ended in misery as his side lost 1-2 at home to Sevilla in the round of 16. Both losses came against FC Basel in 2011 and 2017.
Last season's reverse did not prevent the Reds from progressing to the knockout rounds, though. "I never listen to stupid things like this they say".
The 20-year-old managed just one Manchester United start, playing a total of 122 Premier League minutes, before being England's match-winner twice during the global break.
"We managed to win two hard away matches which was important for us, so I'm happy but I was happy after the Tottenham defeat. with numerous things that I saw".
Earlier, NAIJ.com had reported how Premier League giants Manchester United are reportedly ready to submit £100 million offer to Juventus for the possibility of luring Paulo Dybala to Old Trafford.
"I am really happy to play for this club, one of best clubs in world, so for me it's really good to be part of this club".