Jurgen Klopp: Mitch Langerak was selected for his smile

Jurgen Klopp revealed he decided to give Mitch Langerak a rare chance in goal in Borussia Dortmund's 1-0 win over Hoffenheim on Friday night because of his happy-go-lucky attitude.

Dortmund claimed only their fourth win of the season in the Bundesliga courtesy of Ilkay Gundogan's goal, and moved off the foot of the table.

Klopp had made the decision to bench longserving Germany goalkeeper Roman Weidenfeller for the match, with 26-year-old Australia international Langerak given a rare chance to shine.

"It was a gut decision," Klopp told Sky. "I wanted Mitch's light-hearted attitude and looseness in goal today. He has been working hard for months for this moment."

Asked about the comments after the game, Langerak told the club's official website: "I just heard that story. I always smile once a game is over, as long as we won. During a match, however, I'm all focused and do not laugh."

He said Klopp had told him at training on Friday morning that he would play, adding: "I had a hunch before, but I only knew for sure on the day of the game, but that's not a problem as I'm used to it. As a No. 2 goalkeeper, you always have to be ready to play."

Weidenfeller, 34, has not been at his best this season but Langerak -- who did not have to make a single save against Hoffenheim -- is uncertain whether he will keep his place for Tuesday's Champions League game at home to Anderlecht.

"I don't know," he said. "I'll keep working hard, and hopefully will start another game, but we haven't talked about it yet. I think the decision was only made for this week. Next week there will be a new decision, but that doesn't only apply to goalkeepers but to all positions."

Meanwhile, Klopp has said he was "exhausted and relieved" after claiming only a second Bundesliga victory since they defeated Freisburg on Sept. 13.

"It was a deserved win for us, but no more than that," the coach said. "Most importantly, we scored a goal and didn't concede one. Hoffenheim could have been awarded a penalty, but we were denied a perfectly good goal at 1-0. In our situation it would be nice to see that the goals we score count."