BERLIN - Champions Borussia Dortmund's chase of leaders Bayern Munich faces its toughest test with improved VfB Stuttgart lying in wait on Saturday.

Bruno Labbadia's Stuttgart side have won four of their last six games to move up to fifth spot on 17 points, two behind Dortmund in second.

"We are looking forward to a great game," said coach Labbadia after his team advanced to the German Cup third round with a trouble-free 3-0 defeat of FSV Frankfurt on Wednesday.

"This was an important win for us. The match against Dortmund will be completely different."

Dortmund have won their last four league games including last week's 5-0 demolition of Cologne, and they look to have rediscovered their form after a stuttering start to the season to move three points behind Bayern.

"It is normal that we as German champions attract special attention but we will not be pressurised and will try to play the style that has made us strong and successful," said Dortmund midfielder Sven Bender.

Striker Ivan Perisic is available after sitting out a suspension but Dortmund coach Juergen Klopp is likely to stick with Robert Lewandowski who has netted seven times in 10 league games, including twice against Cologne.

The Pole was also on target in their 2-0 win over Dynamo Dresden in the German Cup on Tuesday, his 11th goal in 15 games in all competitions.

Bayern, who crushed second division Ingolstadt 6-0 in the Cup on Wednesday, should have an easier task than Dortmund. They host Nuremberg (13th) in the Bavarian derby and Bayern coach Jupp Heynckes will recall several top players after resting them in midweek.

Third-placed Schalke 04, who struggled to beat second-division Karlsruher SC 2-0 on Wednesday, entertain Hoffenheim, who are eighth on 16, two points behind their opponents.