Before the season started, I was mystified at the high ranking of so many rookies. I even said to a friend that to justify the lofty expectations, this rookie class would essentially have to break records. As it turns out, it was well on its way to doing so (and still might).

Amongst those leading the charge was Vikings rookie RB, Dalvin Cook. Cook was averaging an impressive 4.78 yards per carry and was well on his way to an RB1 season. That all came to a screeching halt on Sunday when Cook planted the wrong way on his left leg and his knee gave out. We all knew instantly what it meant. No doctor's report was necessary to know that Cook had played his last snap in 2017.

As unfortunate as it is, the show must go own for both the Vikings and fantasy owners. Let's look at how Dalvin Cook's season-ending ACL injury impacts the Vikings and the rest of the fantasy football landscape at running back.

The Replacements

The Vikings offensive line is much improved from last year. They have been a top five run blocking unit in 2017 after being the second worst in 2016. That has shown in Cook's performance. The question remains how much of the Vikings increased effectiveness running the ball can be attributed to Cook himself. We're about to get our answer.

The most obvious candidate to replace Cook is the man that was supposed to be the lead back before the Vikings drafted Cook. Latavius Murray missed most of the offseason recovering from ankle surgery and has recently stated he's still not yet 100%. However, he is certainly healthy enough to handle lead duties. In his two years as Oakland's lead back, he averaged 4.0 yards per carry with 18 touchdowns in 30 games. He was a very effective running back. He will likely form a committee with Jerick McKinnon, who is not built to be the main back, but has flashed explosiveness when used as a satellite back.

McKinnon is still just in his fourth season and lest we forget, he recorded the highest SPARQ score in NFL history. His athleticism is amongst the best of all time. He doesn't have a single workout metric below the 92nd percentile. The man is an athletic freak. With that being said, he averaged just 3.39 yards per carry in 2016 and scored just four total touchdowns (two rushing, two receiving) despite Adrian Peterson missing essentially the entire season. McKinnon rotated with the useless Matt Asiata, which is both an indictment on Mike Zimmer and McKinnon himself. Neither McKinnon nor Asiata were fantasy useful for the majority of 2016.

The Answer

The answer is that there is no clear answer. We have a brief sample size of what the Vikings intend to do in looking at what they did during the game Cook went down. Murray saw 20 snaps. McKinnon saw five snaps. I do not think the split will be that drastic going forward. I expect a 60-40 split and if McKinnon can showcase that elite athleticism, he can certainly earn more playing time. Murray is definitely the priority target on the waiver wire. He is the first player this season that is truly worth a huge chunk of your budget. You have the shot to essentially pickup an RB2. Even if you get it wrong, that gamble is worth it. McKinnon is worth less, but he is far from worthless. I expect McKinnon to be worth rostering all season as a bye week fill in or an RB3 with the obvious upside for greater things. He should get the majority of targets in the passing game, so if you're in a full PPR league and want to spend less for a flex play, you may want to aim for McKinnon.

With the Vikings' improved offensive line and the reports that we should only have to endure two more weeks of Case Keenum, at most, there are reasons to believe that Murray and McKinnon will be a far more effective duo than Asiata and McKinnon were last year. Neither of them will be Dalvin Cook, so Cook owners are not going to be able to get their RB1 back, but it is likely they can recoup at least half of the value in Murray. However, it will cost a hefty chunk of fake money. I anticipate Murray going for over 50% of FAAB budgets and I can't say I disagree with it.

More Waiver Wire Pickups and Analysis