According to the blog from Marcus Fuller-
http://blogs.twincities.com/gophers/2010/08/mbakwe-says-on-his-facebook-pa.html
Canadian doctors diagnosed junior guard Devoe Joseph with a strained quadriceps while he was playing for the Canada men's development team. He only played one game on the European tour and struggled. I've heard that his injury could be more serious and different than first thought, possibly a pre-existing knee injury that grew worse since the end of last season.
Joseph will likely miss the Canada trip, which is a shame since he's returning to his native country. But that is the least of the Gophers' worries. If he needs further medical attention, then will he be 100 percent healthy when camp begins in October?
http://blogs.twincities.com/gophers/2010/08/mbakwe-says-on-his-facebook-pa.html