Berlin: Bundesliga leaders Borussia Dortmund, in formidable form, will be looking to extend their unbeaten run of 21 league games against VfB Stuttgart on Friday (1830 GMT).   

Playmaker Mario Goetze has returned to training after more than two months out with a groin injury and extended his contract to 2016 this week, but will not play against Stuttgart.   

However, the 19-year-old Germany international's imminent return will only boost Dortmund's chances of a second successive league title.   

"As things stand now everyone else is fit and ready for Stuttgart," said Dortmund coach Juergen Klopp, who will also be without injured Felipe Santana.   

Goetze was key in last season's title run and had been outstanding until his injury in late January.   

His comeback in time for what could become a title decider against second-placed Bayern Munich on April 11 is good news for the champions.     

Five points clear of Bayern with seven games left, Dortmund take on Stuttgart having won 10 of their last 11 league matches and extended their unbeaten run to 21 games. They could open up an eight-point lead, with Bayern in action on Saturday.   

The Bavarians have been in spectacular form themselves and enjoyed a 2-0 Champions League quarter-final first-leg win at Olympique Marseille on Wednesday.   

They are expected to have an easier task at relegation-threatened Nuremberg in their Bavarian derby (1330) but sports director Christian Nerlinger warned that the crowded schedule, which also includes a German Cup final against Dortmund in May, could take its toll.   

Bayern, chasing a treble of titles, have won their last three league games, scoring 15 goals in the process, and are on track for a Champions League semi-final clash with Real Madrid.   

"We will need to reach our limits for the next four or five weeks," Nerlinger said. "That will be a mental as well as physical challenge. We are in the final stretch in all competitions and the team is motivated."   

On Sunday third-placed Schalke 04, on 53 points, four behind Bayern, travel to Hoffenheim (1530) while Borussia Moenchengladbach, on 51, are in action at Hanover 96 (1330).