Seville: Barcelona head coach Ronald Koeman defended Samuel Umtiti after the defender made errors on both of Sevilla's goals in Thursday's Copa del Rey match.
Jules Kounde dribbled straight through Umtiti in the first half on the way to scoring Sevilla's opener, while Umtiti kept Ivan Rakitic onside before the Croatian scored his side's second in the 85th minute against his former club.
Sevilla won the semi-final first leg 2-0, leaving Barca with plenty of work to do in the second leg at Camp Nou on March 3.
"We left a lot of space in the first goal, not just in defence, but from the midfield," Koeman was quoted as saying by a website.
"And in the second goal, we have not done a good job creating the offside. Umtiti was good in the game. He made mistakes like everyone else does. It is part of football. It's not fair to go after him. We all lose and we all win together," he added.
Umtiti has struggled through a difficult time at Barca recently, making just 18 total appearances last season as he battled injury and poor form.
He has now started in five of Barca's last six matches in all competitions as he looks to rebuild his Camp Nou career.
Barcelona will face Alaves in La Liga on Sunday before a much-anticipated Champions League last-16 first leg against PSG on February 17.
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