Borussia Dortmund visits struggling Hertha Berlin on Saturday in the Bundesliga without injured playmakers Shinji Kagawa and Mario Gotze, as the top three clubs all face road challenges this weekend.

Dortmund is undefeated in 15 straight games, but its cushion atop the table is just two points over Bayern Munich, and three over Monchengladbach.

Although the trio all play teams in the bottom four of the standings, dropping points this weekend could shuffle the order after 22 matches.

Dortmund lost Kagawa to an ankle injury this week, leaving it without its best playmakers, as Gotze remains out with a groin injury. But Hertha has lost four in a row, and sits just three points off the bottom.

Bayern visits last-place Freiburg on Saturday, as it tries to build momentum for its trip to Basel in the Champions League last 16 on Wednesday. But Bayern defender Jerome Boateng said this week "we can't let that get on our minds."

Coach Jupp Heynckes has limited options in defense with Daniel van Buyten out, but Thomas Muller has regained good form and Arjen Robben could earn a larger role after starting on the bench the last two games.

Heynckes is prepared for a tough match, although Freiburg has just 17 points.

"We can't simply show up in Freiburg and expect to win," Heynckes said.

Monchengladbach has quietly remained near the top of the standings and it goes to 16th-place Kaiserslautern, which has lost its last two games and is winless in its last 11.

Werder Bremen, well behind the top clubs in fifth, visits improving Hamburg on Saturday, when Bayer Leverkusen hosts Augsburg and Nurnberg hosts Cologne in the day's other matches.

On Sunday, fourth-place Schalke will try to remain with the top group when it hosts Wolfsburg, and Hannover hosts Stuttgart in another meeting of top-half sides.

On Friday, Mohamed Zidan just before the half-hour mark to erase an early own goal and Mainz tied Hoffenheim, 1-1, at Rhein-Neckar-Arena.