BERLIN — Robert Lewandowski scored a hat trick Friday as Bayern Munich began its German Cup defence with a comfortable 5-0 win at fourth-tier side Carl Zeiss Jena.

The Poland striker got Bayern off to a flying start in the third minute, scoring at the second attempt with his right boot after Thomas Mueller returned his wayward first effort.

The gulf between the sides was clear and it seemed only a matter of time before the visitors scored again. Lewandowski claimed his second in the 34th, firing home after Justin Gerlach failed to deal with Franck Ribery's cross.

Lewandowski, who celebrates his 28th birthday on Sunday, completed his hat trick nine minutes later with a second assist from Ribery.

Jena resisted in the second half until Lewandowski set up Arturo Vidal in the 72nd — the Chilean had hit the crossbar and would go on to hit the post.

Substitute Mats Hummels wrapped it up in the 77th with his first goal for Bayern, a header to Joshua Kimmich's corner.

"It feels very good," said Hummels, who switched from Borussia Dortmund in the off-season. "Scoring a goal is the best for a defender too."

Bayern coach Carlo Ancelotti's previous visit to Jena didn't go so well.

The Italian, then a 21-year-old midfielder, was part of the Roma side that lost 4-0 to Jena in the second leg of their Cup Winners' Cup tie when the German side overturned a 3-0 loss on Oct. 1, 1980.

"We lost 4-0 and were lucky because we could have lost 10-0," Ancelotti remembered before Friday's game. "The loss is unforgettable. When I hear Jena, I always think of this game. I'm happy to go back after 36 years."

Founded by workers from the Carl Zeiss optics factory, Jena had emerged after the Second World War to become one of East Germany's most important clubs, claiming league and cup titles before its appearance in the 1981 Cup Winners' Cup final.

Like many former East German sides, it has fared badly in the new league system since German reunification, running into financial difficulties and suffering several demotions.

Also Friday, Augsburg won 2-0 at fifth-tier Ravensburg and second-division St. Pauli won 3-0 at fourth-tier Luebeck.

Koo Ja-cheol scored in the first half for Augsburg before Raul Bobadilla ensured the Bundesliga side's progress, while St. Pauli had Vegar Eggen Hedenstad, Soeren Gonther and Marvin Ducksch to thank for its progression.