I `m not sure about this season but almost every year top teams are forced to play every other day during the 3-4 weeks of the season. And this after an long 8-9 months season with two games per week.
There only so much a body can take , even the super fit pl players.
Injuries are common ,sure Besides before every major tournament thee were problems with injureis. But this time it makes a bigger impression cause victims are the best players of their NTs.
Drogba , Essien , Ballack (not the best but he was consiered as the leader of the team). Tores will miss a few games too
Moras is injured too but who cares !!!