Ryan Giggs felt Wales' defeat to Denmark was a "learning curve" for his young players.
Tottenham's Christian Eriksen scored in each half as Denmark ran out comfortable 2-0 UEFA Nations League winners.
"It wasn't easy after the highs of Thursday to get back up again," Giggs said, referring to their 4-1 opening Nations League victory against the Republic of Ireland.
"Against a very good team and physically with the quick turnaround we found it difficult.
"But the lads lads kept going and for the young players it's a learning curve.
"I tried to freshen up it as much as I could and also keep that rhythm of playing so well.
"But you had a team who played two competitive games in a short space of time and a team that didn't - and it showed in the end."
Gareth Bale captained Wales for the first time in his 72-cap career as veteran defender Ashley Williams was rested following Thursday's outing.
Real Madrid star Bale was not at his best, but Giggs dismissed the suggestion that the decision was a mistake.
"I don't think it affected his performance," he said.
"I just felt he was the most experienced. He leads by example and he's very vocal in the dressing room.
"When Gareth speaks, especially the young players listen and it wasn't a difficult situation.
"I could have picked others, Chris Gunter or Aaron Ramsey, but I felt Gareth was best suited to do the role from the rest of the players.
Denmark were in control from the moment Eriksen opened the scoring after 32 minutes with a low drive which went in off a post.
And Eriksen made it 15 goals in his last 18 international appearances with a 63rd-minute penalty after Ethan Ampadu had handled Viktor Fischer's cross.
DENMARK: Schmeichel, Kjær, Delaney, Eriksen, Braithwaite, Jørgensen, Dalsgaard, Stryger Larsen, Schone, Poulsen (Cornelius, 86 mins), Sisto (Fischer, 46 mins). Unused subs: Lossl, Ronnow, Boilesen, Vestergaard, Knudsen, Christensen, Christiansen, Jensen, Norgaard, Lerager.
Wales: Hennessey, Gunter, Chester, Mepham, B Davies, C Roberts (Brooks, 59 mins), Ampadu (T Roberts, 71 mins), Allen, Ramsey, Lawrence (Woodburn, 79 mins), Bale. Unused subs: Ward, A Davies, Dummett, King, Vokes, Ledley, Wilson, Lockyer, Smith.
Referee: Deniz Aytekin (Germany)
Man of the match: Christian Eriksen