You get one move generally out of a corner before it's considered blocking. Since Borg was leading he had rights to drive his car anywhere (once). Until Magnussen gets his nose with Borg, he should be backing down. Once Mag gets to Borg, he tries to steer away from the wall and that puts him in the oversteer. It would have been a disjustice for Magnussen to win if it sent Borg wide on the final turn. Magnussen's only chance was dive bombing and chopping Borg on those final laps, once even resulting in penalty. IMHO...