Christian Pulisic helps Borussia Dortmund beat short-handed Hamburg

American teenager Christian Pulisic scored his first Bundesliga goal to help Borussia Dortmund beat nine-man Hamburger SV 3-0 on Sunday.

Hamburg finished the match short-handed after a red card for goalkeeper Rene Adler soon after the interval and a left-knee injury for midfielder Albin Ekdal.

Pulisic, who has already played for the United States, broke the deadlock in the 38th minute and produced a good performance on the left flank as Dortmund rested several regulars. At 17 years, 212 days, Pulisic became the fourth youngest player to score in the Bundesliga.

The win left Dortmund seven points behind leader Bayern Munich, with four rounds left. Bayern can seal the title if it wins at Hertha Berlin and Dortmund loses in Stuttgart next weekend.

In the late match, Mainz suffered a setback in its hopes of gaining a slot in the Europa League by allowing visiting Cologne to come from two goals down for a 3-2 victory. Mainz stayed in sixth and last slot for the second-tier competition but failed to go three points clear of Schalke.

Adrian Ramos added two goals for Dortmund, one of them coming after Hamburg lost Ekdal to injury and coach Bruno Labbadia was left without another substitution.

Adler was sent off in the 52nd after rushing out of the penalty box and bringing down Shinji Kagawa. Ekdal limped off in the 79th.

"After the red card, the game was over for us," Labbadia said. "We should have scored from some early chances and then maybe we could have earned something here."

Dortmund coach Thomas Tuchel rested eight players from the side that lost 4-3 to Liverpool in the quarterfinals of the Europa League and Hamburg had some early chances.

But Pulisic's goal put Dortmund firmly in control. Pulisic picked up a pass from captain Mats Hummels and drove inside the near post from some 14 meters (yards) with a well-placed low shot.

"It was super, well played by Mats," Pulisic said.

Ramos added the second in the 44th, collecting a long ball from Nuri Sahin and sending it past Adler, this time inside the far post.

The Colombian completed the win in the 86th, knocking in a ball parried by substitute goalkeeper Jaroslav Drobny, whose save from Kagawa landed at the feet of Ramos.

"It was tough, but we won 3-0 and we'll take it," Tuchel said.

In Mainz, the home team dominated for about 50 minutes and led 2-0 after goals from Jhon Cordoba in the eighth and Leon Balogun in the 49th. But Mainz fell apart after Marcel Risse pulled one back for Cologne in the 64th. Substitute Milos Jojic notched the equalizer from close range in the 74th and Anthony Modeste secured the win in the 82nd after picking up a long ball.

Dortmund plays Hertha Berlin in the semifinals of the German Cup on Wednesday, while Bayern meets Werder Bremen a day earlier.