Arsene Wenger believes Manchester United's fixture schedule has given them an unfair advantage in the Premier League title race.
Wenger has reignited a row orginally started by Liverpool boss Rafa Benitez by highlighting the extra time Sir Alex Ferguson's team have to recover from their midweek match next week.
The Arsenal manager is unhappy that league leaders United, who are six points ahead of the Gunners, play West Bromwich Albion on Tuesday, while Wenger's men face Everton on Wednesday - meaning they have only two days to recover before their next game at home to West Ham on Saturday.
As if that wasn't enough to irk Wenger, United aren't scheduled to play again after their Albion match until the following Monday, although that home fixture against Everton could be postponed if either team has to play an FA Cup fourth round replay.
Wenger's comments follow a furious attack from Benitez on Ferguson earlier this month sparked by what he perceived as the United boss's attempts to influence officials and his complaints that United got a raw deal from the fixtures.
"I feel that next week Benitez has a case if you look at the way the fixtures are arranged," Wenger said on Friday. "You can say that Manchester United have been extremely advantaged. It is difficult to explain why one team plays on Tuesday and the others are all on Wednesday. It is unfair competition.
"I do not think you need to be a specialist in football to understand that in this case it is an unfair advantage for Manchester United. "I supported them (United) when they had a case but this week, I think Benitez has a case. "Will it have an advantage on the global season? I don't know, you would have to analyse that better in time."
Unlike Benitez, Wenger opted not to make his attack personal against Ferguson and blamed the Premier League and the television company who show the English top-flight matches for the situation.
"It is not Manchester United's fault, it is not Liverpool's fault. It is the organisation of the fixtures," Wenger said. "You can only accuse Sky of choosing the games, the guy who did it three months ago choosing West Brom against Manchester United to be on Sky, he certainly has a case to explain."