Paris Saint-Germain's star summer signing Lionel Messi was on Tuesday ruled out of their Champions League clash at RB Leipzig.
The 34-year-old Argentine limped off at the end of the first half of Friday night's game against Lille due to a muscle strain in his left leg.
Tests have revealed problems with his left knee as well.
Messi scored twice during the game against Leipzig at the Parc des Princes a fortnight ago as the hosts recovered from 2-1 down to win 3-2.
Kylian Mbappé - who missed a penalty late in the match - is expected to return from the viral infection which kept him out of the 2-1 victory over Lille to lead the PSG attack on Wednesday night with Neymar and Angel Di Maria.
Marksman
Messi has scored three of PSG's six goals in their three games in Group A of this season's competition.
Mauricio Pochettino's men lead the the pool with seven points and victory at the Red Bull Arena would allow them to plant one foot in the last 16 where they have featured for the last eight years.
On Monday, Messi revealed in an interview with Spanish media that helping PSG to win the Champions League was one of the main reasons why he came to the French capital after leaving Barcelona.
“PSG have a great team and I want it to be even better by winning the Champions League," he told the Catalan daily newspaper Sport.
“PSG have come close a couple of times and this season we are among the favourites along with other teams such as Liverpool, Chelsea, Manchester City, Manchester United and Atletico Madrid.”
Chance
In Group A's other game on Wednesday night, second placed Manchester City entertain Club Bruges.
City boss Pep Guardiola potentially riled the faithful in both the blue and red halves of Manchester by describing the tie at the Etihad Stadium as much more important than this weekend's Manchester derby.
"The match against Bruges gives us an incredible chance to qualify for the last 16 of the Champions League," Guardiola said.
"In the Premier League there are many games, in the Champions League just six, and there are not many left. Games three and four are the most important."
Last season's beaten finalists thrashed Bruges 5-1 when the sides met in Belgium on 19 October.
But since then City have been poor by their exacting standards. They lost in the last 16 of the League Cup - a trophy they had won for the past four years - and went down 2-0 at home to Crystal Palace in the Premier League on Saturday.
"I'm pretty sure Bruges will adjust things to punish us," added Guardiola. "We have to adjust to get better. It will be a completely different game."
