Barcelona coach Tito Vilanova says he does not yet know the extent of star attacker Lionel Messi’s injury.
The Argentine left the field on a stretcher during his side’s 0-0 Champions League draw with Benfica on Wednesday, having collided with opposition goalkeeper Artur Moraes.
Messi needs just two more goals to beat Gerd Mueller’s scoring record in a single calendar year, but Vilanova said he was silenced by the knock – believed to be a bruised knee – on Wednesday.
“He (Messi) was quiet, but also worried, like any other player who had been injured or hit,” Vilanova said.
“We do not know yet what he has done, but after the check-up from the doctors he was even more quiet, but as I said, we still have to wait and see.”
Vilanova added the competition has become more unpredictable in recent years, as shown by the exit of defending champions Chelsea.
Barcelona finished top of Group G, with Celtic also going through.
“Last year was about the Manchester teams. This year again City are out, as are Chelsea, the last winner,” Vilanova said.
“So to say that it is clear which two are going to go through – I think the last two years have shown that it’s more difficult.
“Not just because in Europe is very difficult to beat any team. We are talking about a group stage of six games, and any single mistake can put you out.”
Benfica coach Jorge Jesus said he felt his side had the better of the chances at Camp Nou, and added they had failed to achieve their goal of reaching the last 16.
“We had at least two opportunities to score, and we were in front of (Barcelona goalkeeper) Pinto,” Jesus said.
“First we hit the crossbar with Lima and after with Rodrigo, when we were two against one. We were not able to score.
“The opportunity became easy for the quality of Rodrigo, who works a lot, and it was his role on the field to make space for Lima, but unfortunately we missed it. And answering the question, the man of the match was Pinto.
“The object was (to) go through the group stage. And we didn’t achieve what we wanted. But it also demonstrated that we are a great team and we have a lot of chances to play in the Europa League and play the final. This is our new goal at the moment.
“But do not forget that the main goal is our championship in Portugal, and Monday we have already a classic – Sporting (Braga) against Benfica.”