Chelsea will be wary of dropping points against Southampton as they look to maintain their Champions League place when the two teams meet in the English Premier League.
Blues manager Rafa Benitez will have plenty to ponder with his side set to face Manchester United in the F.A. Cup quarterfinal replay at Stamford Bridge on Monday.
With just a day's rest between the games, Benitez will have to make the decision on who plays against Southampton, an equally important game considering Chelsea's need to qualify for the Champions League next season.
"Physiologically, it's impossible," Benitez said of playing two games in two days. "The day after a game you feel really tired, but two days afterwards you feel even more tired. It's the reality. This second day will be really tough for everyone.
"We can't play two different teams. I try to keep the level. The difference is that they (Manchester United) are 15 points ahead, so maybe they can say, 'OK, we do that and see what happens.'
"We can't do that. We have to find a very competitive team for Southampton, with the other game in our head because we can't forget we have just 48 hours.
"I don't want to use this as an excuse because some people say, 'oh, he's making excuses.' No. The reality is that, because of their position in the table, they have an advantage and they will not have another (European) competition ... they are not in the Champions League. For them, it's clear. The priority will be the F.A. Cup.
"For four months, we have been playing one game every three or four days more or less, we know how to handle this, but two days? It's impossible to have fresh legs if you play the 90 minutes against Southampton."
Chelsea have doubts over Gary Cahill and Ramires, but John Terry is coming along from his fitness issues and Benitez will have to make a decision on which game to play the skipper in.
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Expected lineups: Southampton: Boruc; Clyne, Yoshida, Hooiveld, Shaw; Schneiderlin, Cork; Rodriguez, Ramires, Lallana; Lambert.
Chelsea: Cech; Azpilicueta, Luiz, Terry, Bertrand; Mikel, Lampard; Moses, Marin, Benayoun; Torres.
Prediction: 1-1