The Bundesliga is back and the standout game of the first matchday after the winter break is second-placed Schalke's visit to fifth-placed RB Leipzig, a game that has all the ingredients for a classic.

Leipzig's Bundesliga form has suffered under the dual demands of domestic and Champions League football and from some untimely injuries to key players, while rumors about the future of Naby Keita may also have an unsettling effect. Ralph Hasenhüttl's side are already 13 points adrift of leaders Bayern Munich and are looking to end a run of four league games without a win.

"The boys have used the winter break to recharge their batteries and now we're looking forward to getting back into Bundesliga action against Schalke," said the Leipzig boss. "They have a great attitutude and are not easy to beat. We'll need a quality performance to get a result."

While Leipzig have been a little short of their best, the team that have replaced them as the winter runners-up are not flying high by accident. Schalke have improved markedly under Dominic Tedesco, not least in tightening up a defense which is now the second best in the Bundesliga. But Tedesco is now looking to the other end of the pitch.

"We want to improve offensively in the second half of the season," he said in his press conference on Thursday. "In some games, we've been unable to raise the tempo when we've needed to."

Read: Exclusive interview with RB Leipzig goalkeeper Peter Gulacsi

Read: Nagelsmann and Tedesco: Revolutionaries or just coaches?

Leon Goretzka has been heavily linked with a move away from the Veltins Arena.

Goretzka sidelined

But they may need to make those attacking improvements without top scorer Leon Goretzka, who only returned to team training after suffering a lower leg injury on Thursday. Leipzig will see the Bayern Munich target's potential absence as a big boost.

However, Tedesco is planning to replace Goretzka with Marko Pjaca for the Croatia winger's Bundesliga debut.

The talented 22-year-old has joined on loan from Juventus until the end of the season and already netted his first goal for the Royal Blues when he opened the scoring in a 2-1 friendly win against Belgian side Genk.

"Marko has a lot of qualities and he is an option to start against Leipzig," said Tedesco.

"If he had not been injured then he would surely have played more at Juventus. He offers up a lot of different qualities and is fit. He gathered the game time in the second team and played very well in those games. The fact he has come to us 100 precent fit is a big credit to him.”

Bayern will have to find a way to stop Leverkusen striker Leon Bailey, one of the revelations of the season

Elsewhere on matchday 18

— Bayer Leverkusen vs Bayern Munich: Another eye-catching game is Bayern Munich's Friday night visit to BayArena to face a Bayer Leverkusen side who are also mounting a top four challenge this season under Heiko Herrlich. Bayern eased to a 3-1 win over Leverkusen in the corresponding fixture on the opening day, but Leverkusen — unbeaten in 12 — could give Bayern a run for their money this time, with the champions missing injured duo Robert Lewandowski and Mats Hummels.

— Wolfsburg vs. Borussia Dortmund: The last game of the weekend could be one of the most intriguing. Borussia Dortmund showed signs of life immediately after Peter Stöger took over from Peter Bosz, but the pressure is on them to string together a few wins. They face a Wolfsburg side who are winless in three and ended the year by becoming the first — and so far only — side to lose to Cologne in the league this season.

— Cologne vs Borussia Mönchengladbach: For the aforementioned Cologne, the winter break came at a bad time as they finally recorded that Bundesliga win. They desperately need another to generate some kind of momentum to close that huge nine-point gap to Hamburg. The problem is that they are facing Mönchengladbach, who have won eight of their last 11 Bundesliga meetings with the Carnival club.

Matchday 18 fixtures

Bayer Leverkusen vs. Bayern Munich (Friday, 20:30 CET)

Eintracht Frankfurt vs. Freiburg (Saturday 15:30)

Augsburg vs. Hamburg

Stuttgart vs Hertha Berlin

Werder Bremen vs Hoffenheim

Hannover vs Mainz

RB Leipzig vs. Schalke (Saturday 18:30)

Cologne vs. Borussia Mönchengladbach (Sunday, 15:30)

Wolfsburg vs Borussia Dortmund (Sunday 18:00)