Jose Mourinho was delighted with Manchester United's change in attitude after they bounced back from defeat at Huddersfield to beat Swansea 2-0.
United progressed to the Carabao Cup quarter-final thanks to goals in either half by Jesse Lingard, coming days after their below-par showing at Huddersfield in the Premier League.
Mourinho, who made seven changes for the trip to south Wales, praised his side's performance, and described the win as comfortable, but not easy.
He told Sky Sports: "Again, like in the match against Huddersfield, where mistakes were part of a global attitude, today the kids' good performances had consequences, we were solid, compact and in control.
"Since the first minute we felt we were in the game, we had immediately some corners, pressing high and comfortable on the pitch. The attitude was good.
"But I don't think [it was easy] I think they have a good squad, a squad with lots of options. We were really comfortable, the attitude was really good, I think Romero and Smalling gave us big stability.
"I'm really happy. It was quite comfortable, no injuries, so a good day for us."
Mourinho started youngsters Scott McTominay and Axel Tuanzebe, and singled out midfielder McTominay for the highest praise after his assured performance.
"I think they both did well, I would say Scott probably very well, because he was really comfortable and strong in midfield.
"Axel I think started a little bit shaky, but then did get some stability and also put in a good performance."
It was Mourinho's 400th match in English football, and the 54-year-old says his desire to win is exactly the same as it was 13 years ago when he joined Chelsea from Porto.
"Of course I am [still getting the buzz]. But you know, 2004 was a long time ago, I think I am obviously the same but more mature, with a different way of reacting to things.
"But I'm the same, I want to win and I hate to lose."