Lionel Messi test results leave PSG sweating ahead of Man City clash

Paris Saint-Germain are sweating on the scan results of Lionel Messi's knee injury amid worries that he could be set for a longer layoff than first feared.

The Argentine superstar was substituted off in Sunday's Ligue 1 victory for Paris Saint-Germain against Lyon as it subsequently emerged that he was carrying a knee injury.

The 34-year-old sat out Wednesday's Ligue 1 victory at Metz and is also a major doubt for this weekend's league clash against Montpellier.

The six-time Ballon d'Or winner had been feeling pain in the upper part of his left knee and will undergo medical examinations on Thursday to fully evaluate the extent of his injury.

Lionel Messi was forced off during Sunday's Ligue 1 clash against Lyon ( Image:

AFP via Getty Images)

It has since been clarified that Messi has suffered bone contusion - bruising on the bone of the knee - which will now be subject to an MRI scan.

These injuries are caused by impact on the area which subsequently leads to an inflammatory reaction and could potentially cause internal bleeding in the area, which would not be evident until days after the initial blow.

It has been suggested by a Spanish medical outlet that the initial injury may have been sustained in Argentina's clash against Venezuela last month.

It is speculated that Messi initially picked up the injury from the kick he received from the Venezuelan player Luis Adrian Martinez - even though he did not initially feel the full force of the injury and was able to continue on the pitch.

PSG became aware of the injury last week but there are indications that it is worse than first feared, with Messi substituted off for just the 17 th time in his club career in the second half against Lyon.

It is claimed that the player felt pain in the area after the match that was sufficient to see him miss full-time training with his teammates - although this may have been a precautionary measure.

Poor treatment of the injury can lead to a more serious situation, such as bone edema - when fluid builds up in the bone marrow.

Such concern may lead to Messi missing several weeks of action, with the player now a real doubt for next week's home match against Manchester City in the Champions League.

PSG are already under a degree of pressure in their Champions League group following an underwhelming opening day draw against Club Brugge.

In a group that also contains Bundesliga outfit RB Leipzig, there is now pressure for Les Parisiens to pick up maximum points in their home matches and they host Pep Guardiola's team next week.

PSG boss Mauricio Pochettino said on Messi's injury: "I took the decision to take Leo off to protect him for possible injuries. We have important games coming up and we want to protect him.

"These are decisions (the substitution) that we make for the good of the team.

"Sometimes the players agree and sometimes they don't. Afterwards, Messi told me he was fine with the decision."