Porto's leading scorer Vincent Aboubakar is doubtful for their Champions League match at home to Liverpool, coach Sergio Conceicao said Tuesday.
The Cameroon forward missed Porto's last league game against Chaves with a muscle problem, although the club have not given further details about the injury.
Aboubakar, who has returned to Porto after spending last season on loan at Besiktas, has scored 26 goals in all competitions this season, including 15 in the league and five in the Champions League group stage.
Asked if Aboubakar would play in Wednesday's match, Conceicao replied: "It's unlikely."
Conceicao also confirmed that defensive midfielder Danilo, who suffered a calf muscle injury during the match against Sporting on Jan. 24, would not be fit in time for the round of 16 first leg tie.
The Portuguese league leaders are underdogs and Conceicao said that one of their disadvantages was that Liverpool were more used to playing top-level games.
"The tests they face every week are much more demanding than the ones we have here in Portugal," he said. "With all due respect to the Portuguese league, Liverpool play at a difficult level to us.
"But we will do everything we can to get to the next round. We have already passed some severe tests in the Champions League and this squad allows us to think that it's possible."
He said that a good result on Wednesday would be "a win without conceding a goal."
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