Borussia Dortmund's title credentials will be put to the test tomorrow when fellow challengers RB Leipzig visit Signal Iduna Park.

Only goal difference separates BVB from the Bundesliga's summit, though reigning champions Bayern Munich will hope to extend their lead once again at Stuttgart on Saturday.

Upstarts Union Berlin were convincingly beaten by FCB last weekend, so will be hoping to get their quest for top spot back on track against FC Cologne.

Top-four hopefuls Freiburg travel to Borussia Monchengladbach, while the division's bottom two teams meet when Bochum host Schalke.

Game of the week: Borussia Dortmund vs RB Leipzig (Friday, 7.30pm)

Dortmund are in sensational form having won all seven of their Bundesliga matches in 2023.

That is the club's best-ever start to a calendar year and — perhaps unusually for BVB — a rock-solid defence has been at the heart of their success. No team in Germany's top flight has kept more clean sheets than their nine to date.

But Leipzig should certainly be a match for their hosts — they have picked up more points since Marco Rose was appointed in September than any other side in the division (37).

Curiously, both these teams have scored (45) and conceded (27) exactly the same number of goals, hinting that a close game could be in store this evening.

With four strikes in his last four league fixtures, Dortmund's Julian Brandt may well be the difference-maker in North Rhine-Westphalia.

Stuttgart vs Bayern Munich (Saturday, 5.30pm)

Bayern Munich issued a reminder of their quality against Union Berlin last Sunday — but Stuttgart could prove to be tricky opponents this weekend.

After all, Die Schwaben have picked up results in their last two encounters with Julian Nagelsmann's outfit, drawing on both occasions.

Fortunately for Bayern, their longer-term record against Stuttgart makes for more pleasant reading. They have won 67 of their 107 Bundesliga meetings, which is a league record against one single opponent.

Thomas Muller will be desperate to make a decisive contribution at the Mercedes-Benz Arena. He is just one goal or assist away from recording 300 career top-flight goal involvements (141 goals, 158 assists).

Union Berlin vs FC Cologne (Saturday, 2.30pm)

Union were brought down to earth by Bayern on Matchday 22, though a home clash with Cologne could be the perfect tonic for Die Eisernen.

Saturday's visitors have not won any of their previous nine competitive meetings with the capital club and are yet to beat them in the Bundesliga (one draw, six defeats).

Cologne's away record this season will not boost hopes of them securing a victory either. They have only won one of their 11 league games on the road in 2022-23 (five draws, five defeats).

However, it would be unwise to rule out a comeback from either of these teams, regardless of how the match appears to be shaping up.

Union and Cologne have claimed the joint-most points from losing positions this term (12), though only Schalke (two) have dropped fewer points than tomorrow's hosts after going ahead (four).

Borussia Monchengladbach vs Freiburg (Saturday, 2.30pm)

Freiburg will have happy memories from their last visit to Borussia-Park, when they recorded a 6-0 victory — the Breisgau Brazilians' biggest triumph in the Bundesliga.

And they may fancy their chances of repeating that feat against a porous Monchengladbach defence.

Daniel Farke's team have conceded 10 goals in their last three league matches (more than any other side) and have only kept one clean sheet in their previous 15 games.

Dead-ball situations may be Freiburg's best route to goal, with Christian Streich's men scoring a league-high 18 times from set pieces this season.

Bochum vs Schalke (Saturday, 2.30pm)

The Bundesliga's bottom two teams go head-to-head at the Vonovia-Ruhrstadion, with the form book favouring Schalke's chances of victory.

Despite sitting in 18th place, Die Knappen are unbeaten in the second half of the season (one win, four draws). Bochum, on the other hand, have lost their last three league fixtures.

But Thomas Letsch's outfit will take heart from their opponents' atrocious away record — S04 are in the midst of a 38-game winless run on the road (12 draws, 26 defeats).

This match-up pits Germany's bluntest attack (Schalke with 16 goals) against the league's worst defence (Bochum with 54 goals conceded). The outcome of that battle could have a decisive impact on the relegation dogfight.

The weekend's other games

Mainz vs Hoffenheim (Saturday, 2.30pm) 

Augsburg vs Werder Bremen (Saturday, 2.30pm) 

Bayer Leverkusen vs Hertha Berlin (Sunday, 2.30pm) 

Wolfsburg vs Eintracht Frankfurt (Sunday, 4.30pm)

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