Robert Lewandowski, the German league's top-scorer, can make his 200th Bundesliga appearance for Bayern Munich in Saturday's tricky away match at FC Union, where Germany's leading clubs have struggled in the past.

In fact, Lewandowski could claim two milestones in Berlin as he is just two short of scoring 250 Bundesliga goals for both Bayern and ex-club Dortmund.

Lewandowski has shaken off a leg knock which ruled him out of Wednesday's 2-0 home win over Lokomotiv Moscow in the Champions League with the holders already through to the last 16 as group winners.

"I assume that he is 100 per cent fit," said Bayern coach Hansi Flick before they headed to Berlin.

Lewandowski, the Bundesliga's top scorer for the last three seasons, once again leads the way with 12 goals so far.

Two of his closest rivals - Dortmund's Erling Braut Haaland, who has 10 goals, and Leverkusen's Lucas Alario, on seven - are sidelined by knee injuries.

Bayern hold a one point lead over Bayer Leverkusen, who they face away the following weekend.

Union's eight-match winning run was ended last Friday by a 3-1 derby defeat at Hertha Berlin.

To make matters worse, Union's top-scorer Max Kruse, who claimed five goals and four assists in November, misses Saturday's game against Bayern with a torn hamstring.

Even without Kruse, Union coach Urs Fischer is looking forward to the "awesome task" of facing the league leaders and European champions.

"We will try to be brave and get through the difficult phases. We must not lose the courage to attack," added Fischer, whose side are sixth.

Union's Swiss coach has just signed a contract extension, reportedly until 2023.

In the two years since his arrival, Fischer has turned Union into a side capable of tripping up sides at the top of the league.

Last season, both Dortmund and Moenchengladbach were first in the table when they lost at Union's packed Alten Foersterei stadium, where Bayern laboured to a 2-0 win behind closed doors in May.

In recent home games, Union saw off strugglers Mainz 4-0, then Arminia Bielefeld 4-0 before Kruse netted twice in a 3-3 draw with Frankfurt a fortnight ago.

Peter Bosz's Leverkusen, who are home to Hoffenheim on Sunday, have climbed to second by joining Wolfsburg as the league's only unbeaten teams.

Part of their success is due to Bosz improving Leverkusen's threat at set-pieces and they scored twice from Leon Bailey corners in Sunday's 3-0 win over bottom side Schalke.

"That is a huge factor for us and cannot be overestimated," said midfielder Julian Baumgartlinger, who scored with a header against Schalke off a Bailey corner.

RB Leipzig's Swedish playmaker is back to his best after a groin strain sidelined him earlier in the year with strong displays against Bayern Munich and Manchester United.

After claiming his first headed Bundesliga goal in last weekend's thrilling 3-3 draw at Bayern, Forsberg was a constant menace in Tuesday's 3-2 home win which dumped Manchester United out of the Champions League.

Third-placed Leipzig trail Bayern by two points before Saturday's home game against Bremen.

248 - the league goals Lewandowski has scored for Bayern and ex-club Dortmund. Only Munich legend Gerd Mueller and Schalke striker Klaus Fischer have previously reached the 250 goals milestone.

330 - the Bundesliga games Lewandowski has played in his career, including 199 for Bayern.

44 - the Bundesliga games Union Berlin have played in the club's history.

Fixtures (all times 1430GMT unless stated)