Leading 2-0 against Manchester United at halftime, Roberto Martinez was forced to replaced Sylvain Distin with Antolin Alcaraz. Distin reportedly suffered a slight hamstring injury, so hopefully the switch was more of a precautionary one rather than anything too serious.
The reaction from most Everton fans, including myself, appears to be mild panic. With Phil Jagielka still not healthy, the thought of losing Distin for the final few matches of the season is not an enjoyable prospect. John Stones has been immense since taking over for the injured Jagielka, but Alcaraz is not a player that inspires coincidence.
While I don't know when the injury was picked up, my best guess was a play near midfield late in the first half where Distin accelerated to beat Wayne Rooney to the ball. Distin appeared to over extend his leg to make the play, and while he wasn't in obvious distress, it certainly looked like the type of play where you could tweak a muscle.
Hopefully Everton can finish off this game against United, and we'll see how Distin's hamstring is over the next couple days.