"We didn't play up to the level that we wanted to," Ter Stegen said. "Thankfully we took the three points, which are very important. We need to talk about things." But the 'keeper did not want to single out individual players for criticism.
"We have to do it (talk) in private, I won't say anything here. There are things we can improve. It's an internal issue and I don't want to speak about it here," the German said. "I would like to talk to my teammates on the field first."
Coming off a 3-0 win at Eibar in the Spanish league, Barcelona appeared in control when Lionel Messi scored just three minutes after kickoff but then found itself outhustled by Slavia. Ter Stegen had to make a save with his leg to deny Jaroslav Zeleny. Moments later Ter Stegen leapt and stretched to palm Peter Olayinka's dipping shot over the bar.
Ter Stegen couldn't stop Jan Boril's equalizer from inside the area five minutes into the second half that was well deserved for the hosts. Messi then floated a cross to Luis Suárez, who knocked the ball off Olayinka and into the net in the 57th to take the tougher-than-expected victory.
"They leveled the score on their first attack of the second half," Ter Stegen said. "That can't happen. He was too alone. We didn't come (out for the second half) at 100%. "Personally I always want to be there if I can help the team play ever better. We saw some counterattacks when we were not well-positioned. Those things happen and that's why I am there."
Barcelona has a three-point lead in a tough Group F which includes Inter Milan and Borussia Dortmund. But that can't gloss over another subpar showing for Barcelona on the road. In their Champions League opener at Dortmund, Ter Stegen stopped Marco Reus' penalty and made several other saves for Barcelona in a 0-0 draw. At home, he also blocked a point-blank header from Inter forward Lautaro Martínez that would have doubled the Italian club's lead, before Barcelona rallied for a 2-1 win in their second match in Europe's top club competition.
"He has been key in our Champions League matches," Barcelona coach Ernesto Valverde said. Barcelona also leads the Spanish league but it has done better at home than away, where it has two wins on the road after stumbling in its first three away fixtures.
Ter Stegen has excelled as Barcelona's first-choice goalkeeper after making the occasional mistake following his move from Borussia Mönchengladbach in 2014. With impressive saves, a cool-under-fire attitude, and also crisp passing, he has helped Barcelona to win one Champions League and four Spanish league titles.
The 27-year-old keeper's consistently strong performances have even let him challenge veteran Germany goalkeeper Manuel Neuer, who has held the position for a decade.
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