Bundesliga
Sebastien Haller has overcome testicular cancer and is gearing up to make his competitive debut for Borussia Dortmund when the Bundesliga restarts for the five-time champions at home to Augsburg on 22 January.
After stepping back onto the pitch during Dortmund's winter training camp, bundesliga.com looks at where the summer arrival from Ajax could fit into Edin Terzic's team.
Watch: Sebastien Haller makes his comeback from cancer
4-2-3-1
Terzic employed this formation the most during the Hinrunde, and it appears ideally suited for a centre-forward like Haller. When Haller's diagnosis was made, Dortmund brought in Anthony Modeste — a similar type of player to the Cote d'Ivoire international — as cover. The Frenchman didn't shine, scoring just two Bundesliga goals, but Youssoufa Moukoko did better.
Despite the youngster's relative lack of height — he measures 5'9" compared to Haller (6'2") and Modeste (6'1") — Moukoko headed the matchwinner in the derby with Schalke, one of a team-leading six league goals he has tallied so far. For now, the 18-year-old Germany international will no doubt fill the role as Haller, who is 10 years Moukoko's senior, still requires time to regain full match fitness. But the France-born forward appears tailormade for Terzic's system of choice, and it was the one in which he excelled — netting 47 times in 66 appearances — for Ajax.
4-3-3
This main difference between this formation and a 4-2-3-1 is in midfield, rather than up front. Mahmoud Dahoud — fit again after a shoulder injury that has limited him to just three league appearances this season — will slot in in front of the back four with two number eights. Jude Bellingham is likely to be one of them with Salih Özcan and Gio Reyna viable options to join the England international. Either side of Haller in the central striker role, Marco Reus — fully fit after the ankle problems that plagued his first half of the season — and Julian Brandt, who has registered four goals and two assists so far, are options out wide, as are Jamie Bynoe-Gittens, Thorgan Hazard and Marius Wolf, with Karim Adeyemi and Donyell Malen providing Terzic with further permutations.
One consideration for Terzic to weigh up is Haller's aerial strength. His height as well as his timing make him a formidable opponent when the ball is crossed into the box, so quality service from out wide is crucial to enable him to either have a goalscoring opportunity or bring teammates into play.
3-5-2
What if Haller had a strike partner? Moukoko would be the most obvious choice to buzz around Haller, who would be the focal point for passes forward. Adeyemi and Malen would also offer alternatives to be half of what could be a hugely effective 'Little & Large' duo.
Watch: The Bundesliga is back!
In this set-up, the undoubted ability on the ball of wing-backs Thomas Meunier and Raphaël Guerreiro would be able to come to the fore as they would provide the width and crosses for the front two, with the defensive duties largely shouldered by the imposing trio of Niklas Süle, Mats Hummels and Nico Schlotterbeck.