USMNT international Sergino Dest has said a lack of confidence has affected his performances for Barcelona in recent weeks.

Dest, 20, joined Barca from Ajax in a deal worth an initial €20 million at the start of the season and, due to an injury to Sergi Roberto, has been an ever-present since, making 21 appearances in all competitions.

- Ratings: Dembele 8/10, Araujo 7/10 as Barca eke past tiny Cornella
- ESPN+ viewer's guide: Bundesliga, Serie A, MLS, FA Cup and more
- Real Madrid's Copa del Rey conquerors' budget under $1m a year

He settled in quickly, impressing in October's Clasico defeat to Real Madrid, but said his form has tailed off over the last month, culminating with a thigh injury that forced him to miss two of Barca's last three matches.

"For me, it's important to get that confidence back because I feel a little bit unconfident right now," Dest told La Liga World.

"That's the most important thing for me right now: get the confidence back and play like I used to play and then I think I have a lot of potential."

Dest sat out the Spanish Supercopa semifinal win over Real Sociedad with a thigh problem and was substituted at half-time in the final last Sunday, a defeat to Athletic Bilbao, after rushing back too soon.

The right-back also missed Thursday's Copa del Rey win against Cornella but returned to full training on Saturday and is in the squad for Sunday's league game at Elche.

"Sergino has played a lot of games and this is just his first season with Barca," coach Ronald Koeman said in a news conference on Saturday.

"He's a very young player and it's complicated for the youngsters. He's been injured but he seems to have recovered and we will decide on Sunday if he starts or is on the bench.

"I hope he has no more problems with injuries, can get some rhythm back and provide competition."

Barca will be without Lionel Messi who is serving the second of a two-game ban for his red card in last weekend's Supercopa final.

Gerard Pique, Sergi Roberto, Ansu Fati and Philippe Coutinho are also unavailable with injuries, but Jordi Alba and Frenkie de Jong return to the squad after being rested against Cornella.

Koeman's side were made to sweat before beating third division Cornella after extra-time with both Miralem Pjanic and Ousmane Dembele missing penalties in normal time.

Barca have now missed seven of 12 penalties taken this season and Koeman said the team had been practicing spot kicks on Friday and Saturday.

"We're analysing the issue with penalties because we've taken 12 this season and have missed seven, including the Supercopa shoot-out," Koeman added.

"That's a lot. It's too much. It's not acceptable. If Messi is not playing, who's the No. 1 taker, we need other players with the quality to score penalties.

"We've been working on them over the last two days. You can train for them just like you practice free-kicks. Of course, it's not the same in training as in a game when you're behind, but there are no fans, so there's no pressure."

Barca are unbeaten in eight league games and have risen to third in the table. However, they remain 10 points behind leaders Atletico Madrid, who also have a game in hand.