Murray did not say Gasquet's movement deteriorated because of supposedly his 'ankle injury'. His move deteriorated because he is not the fittest player out there and he's been known for that for sometime. And I don't necessarily believe into everything
And I like the fact how the 'injury' showed up at the right time just when he lost 2nd set 6-1 and when Andy looked to be supremely confident and in complete control of the match. In other world, what Gasquet pulled, we call it gamesmanship, where the player is desperately trying to stop the momentum and giving himself some time to regroup as a last resort.