Naby Keita is set to undergo tests after sustaining an adductor problem in RB Leipzig's win at Hamburg on Friday.
Liverpool-bound midfielder Keita scored in Leipzig's 2-0 Bundesliga victory, however, he was unable to complete the match.
After opening the scoring past the hour-mark, Keita – who will join Liverpool in the Premier League next season – had to leave the field in the final minute of regulation.
Leipzig will be sweating on Keita's fitness ahead of their Champions League debut against Monaco midweek.
Naby was unable to complete due to an adductor problem. An exact diagnosis will follow in due course. September 8, 2017
Germany international Timo Werner was also on target as Leipzig ended Hamburg's unbeaten start, sealing the victory with 15 minutes remaining.
Werner, though, could have opened the scoring in the first half after being awarded a penalty.
However, the video assistant referee (VAR) overturned the decision, after Werner went down in the box under a challenge from Albin Ekdal.
‘After Manchester City’s recent form, maybe they’re the underdogs against Manchester United!’ Former Red Devils defender on this weekend’s derby
‘Arteta, Alonso, Emery, me… none of us were physical players – we needed the understanding of the game. That probably helped us move into management’: Premier League boss reveals reasons for natural career progression
