Matt Asiata, who has been the Vikings' primary ball carrier since the start of Adrian Peterson's off-the-field issues, took a back seat to Jerick McKinnon Week 6 against Detroit. In fact, Asiata didn't touch the ball until midway through the second quarter, with McKinnon getting each of the Vikings' first six carries.
In all, Asiata got just three touches, losing 5 yards on two carries and gaining 18 on a catch. He was targeted one other time in the passing game but had the ball deflect off his hands for an interception. That was in the second quarter. He made only one statistical contribution after that.
True, he was probable coming into the game with a groin injury, so it's possible his workload was adjusted for his health. Also, McKinnon may not have put the dilemma to rest with his performance, gaining 40 yards on 11 carries. But the rookie is clearly the more explosive of the two and proved viable in the passing game as well, actually leading the Vikings with 42 yards on six receptions.
If you own both in Fantasy, you should probably lean more toward starting McKinnon than Asiata at the Bills in Week 7, but both do need to be owned until we have more clarity here.