I do think lots of players who are injured enter this competition anyway. Tons of them are retired after few sets. Why they entered if they know they are injured? Cause the pay are the best even for first round loss?
Better if they just did not enter French Open and give the chance to healthy lucky loser in qualifier round.
Anyway, I do hope all top seed did not had any serious injury and can play the best of their ability. (looking at Davydenko and Monfils