I don't watch Sportsnet very often, but I almost always PVR TSN's SportsCentre at 5 and 6 p.m. They have way more coverage of the CFL than MLS. It's not remotely close. Obviously now that MLS playoffs are here, with two Cdn teams in them, there is a fair bit of MLS coverage. But from June through end of October I would bet CFL gets at least 10 times the coverage MLS does on SportsCentre, and it may be a much higher ratio than that.
Bookmarks