DORTMUND - Bayer Leverkusen's Josip Stanisic scored a stoppage-time goal for the champions to rescue a 1-1 Bundesliga draw at Borussia Dortmund on Sunday, sparing Xabi Alonso's side from suffering their first loss of the season.

Striker Niclas Fuellkrug gave Dortmund the lead in the 81st minute but Stanisic levelled for Leverkusen in the seventh minute of stoppage time, heading home a Florian Wirtz corner.

The Croatia defender helped extend the newly-crowned champions' unbeaten run in all competitions to 45 games after they secured their first Bundesliga title with a 5-0 victory over Werder Bremen last weekend.

Dortmund, who on Tuesday advanced to the Champions League semi-finals with a 5-4 aggregate win over Atletico Madrid, are fifth with 57 points, two points behind fourth-placed Leipzig

"The goal we conceded hurt, but we kept going and I'm happy with our reaction," Alonso told DAZN.

"We're still waiting for our big party. Now we'll recover a bit and then prepare well for Stuttgart, which will be a very exciting game.

"We just don't want to lose. The goal was very emotional, celebrating with the fans was very nice and it means a lot to us all."

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Leverkusen are on 80 points from 30 games.

Dortmund, who on Tuesday advanced to the Champions League semi-finals with a 5-4 aggregate win over Atletico Madrid, are fifth with 57 points, two points behind fourth-placed Leipzig.

Alejandro Grimaldo came close to scoring for Leverkusen twice towards the end of the first half, both times sending the ball narrowly over the bar, before goalkeeper Lukas Hradecky dived to deny Dortmund's Marcel Sabitzer from close range.

Nathan Tella could have then opened the scoring for Alonso's men from point-blank range in the 68th minute, after Jonas Hofmann squared him the ball inside the box, but Dortmund keeper Gregor Kobel showed off his skills to catch the ball on the goalline.

Despite a narrow advantage on the visitors' side, Fuellkrug put Dortmund in front with a late volley inside the left post, after Sabitzer teed him up with a lovely cushioned pass before the ball went in off Hradecky's gloves.

Things got tense between the players and Leverkusen forward Victor Boniface was initially shown a red card for what seemed an unsportsmanlike conduct but the referee overturned his decision after a VAR check.

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Grimaldo had another great chance from a free kick as he sent the ball towards the upper corner that was denied by a stunning save from Kobel, before Stanisic found the record-saving equalizer less than a minute later following a corner.

Leverkusen have not won any of their last four Bundesliga matches against Dortmund, their longest ongoing winless run against any current top-flight side.