League leaders Bayer Leverkusen’s bid for a debut Bundesliga title is likely to hinge on how well Xabi Alonso’s side account for their Africa Cup of Nations absences.

Unbeaten Leverkusen sit four clear of second-placed Bayern, who have a game in hand, but need to do without the AFCON-bound Odilon Kossounou, Edmond Tapsoba and Amine Adli. A fourth, Nigeria striker Victor Boniface, was set to make his AFCON debut but injured his groin in training and will be out until April after undergoing surgery.

The tournament starts on Saturday and runs until February 11th. That period includes crucial league fixtures at home to Bayern and away at fourth-placed RB Leipzig, as well as a German Cup quarter final with in-form Stuttgart. Alonso’s side have won 22 and drawn three of 25 games this season, thanks in large part to their African contingent.

Boniface has been the standout since arriving in the summer, scoring 10 and assisting seven more in the league. Czech striker Patrik Schick has made a timely return from injury and will need to step up in the Nigerian’s absence. His six goals in nine games in all competitions, at a rate of one goal per 40 minutes including a last-start hat-trick in a 4-0 win over Bochum, will give Leverkusen fans hope.

AFCON will not just impact Leverkusen up front however. Alonso’s side have conceded a league-low 12 goals from 14 matches this season, with centre-backs Kossounou and Tapsoba forming a stable partnership alongside Germany international Jonathan Tah. Tapsoba, who will represent Burkina Faso, told a group of journalists including AFP in December Leverkusen had enough depth to navigate the difficult period.

“We trust our teammates and everyone’s working hard. You can see the coach is trying to mix the line-up every game and I think everybody’s going to take his chance. So we wont worry so much about that.” Alonso shared the sentiment, saying in December “we are losing some players but we have seen that all our players can play.”

“I’m not crying and I’m not a victim. We have enough players.” Leverkusen sporting director Simon Rolfes said last month AFCON should be moved, saying it has an impact on whether clubs sign African players. “For sure all European clubs need to have this in mind” Rolfes said.

“You cannot have 15 African players in your squad and then in January you don’t have any players anymore. We would like to have the Africa Cup in the summer break between the seasons, but it is what it is.”