Unai Emery insists Aston Villa must learn how to handle European football and refused to blame his changes after their sloppy 3-2 defeat at Legia Warsaw.

Ernest Muci’s second-half winner clinched a deserved victory for the hosts to ruin Villa’s Europa Conference League debut.

Jhon Duran and Lucas Digne twice levelled for the underwhelming visitors in the first half after Pawel Wszolek and Muci scored for Legia.

It ranked as one of the worst performances in Emery’s 11 months in charge, with the manager making five changes, including giving a debut to Barcelona loanee Clement Lenglet.

He said: “I believe in our squad and our players and we could have lost this game with other players on the pitch.

“Every match away in Europe is difficult and this is a new step where we have to learn.

“We still have the possibility to react again, we are going to play another five matches. It’s not a good result but we have to learn and have to understand how we’re going to face the next matches and this competition.

“We have to build the squad who will play a lot of matches and we will need players in the squad to give them opportunities to play, to use their qualities.

“In the second half we started well but in one click, we concede another opportunity and they score a goal.

“They had a plan, they did good and we couldn’t stop them in some moments.”

Legia struck after just two minutes in the Group E opener when Wszolek converted Patryk Kun’s cross.

Duran levelled four minutes later, though, nodding in after Kacper Tobiasz turned Nicolo Zaniolo’s drive onto the bar.

It should have given Villa a platform but a shoddy, slow, performance continued to undermine their tag as one of the tournament favourites.

Livewire Muci punished them again after 26 minutes when Villa were left floundering on the flanks and he fired in Wszolek’s centre.

But Villa came back, however undeserved, and Digne’s deflected volley ensured they went into the break level.

Parity did not last long, though, when Muci went sent running at Ezri Konsa and Calum Chambers, made fools of them both and found the net off a post.

This time there was no way back and Marc Gual almost added a fourth when Emi Martinez parried Bartosz Slisz’s shot and Chambers cleared.

Jacob Ramsey, Moussa Diaby and Youri Tielemans tried to find an unlikely leveller but victorious Legia held on.

“You should not underestimate the underdogs, Mostar will also be a hot game, a Balkan team with a lot of emotions,” said boss Kosta Runjaic, after Mostar beat AZ Alkmaar 4-3 in the other group game.

“It’s surprise for me but it’s also a surprise we won against Aston Villa, I’m happy about it, this three points in the first game are very important for us. We were lucky in some moments but you need luck.

“We will see how we do in the next game, we will face a very ugly Alkmaar in a couple of weeks.”