Thomas Rawls had an incredible rookie season. He was the only player, rookie or veteran, with two games with at least 160 rushing yards in 2015. His heat map was otherworldly, with the highlight being that an astounding 10% of his runs went for at least 15+ yards. And he led the league in yards per carry, as Rawls averaged 5.65 yards per carry while rushing for 830 yards. Rawls ranked 1st in DYAR, 1st in Success Rate, and 2nd in DVOA according to Football Outsiders.

In the historical context, Rawls also stands out. The table below shows all rookies since 1970 with at least 700 rushing yards and 5.00 yards per carry: there are only 18 of those players, and Rawls has the second highest YPC average in the group:

That’s some pretty good company, although there are some less-exciting comps on the list, too. But here’s another interesting thing about his season: Rawls went undrafted in 2015. Rawls ranks 4th among all undrafted free agents in rushing yards gained as a rookie, behind only Dominic Rhodes (1,104), Blount (1,007), and Grant (956).

It’s too early to get a sense of whether Rawls will be the next Ivory (or better) or the next Blount (or worse). I’d say his heat map is a positive sign, as he was consistently gaining yards. On the other hand, the sample size is tiny here; Bills rookie Karlos Williams had almost the same YPC and three more touchdowns on about 2/3 as many carries. Andre Ellington wasn’t far off Rawls’ rookie numbers, either. But if you want to play with the cut-offs, you could also generate this stat: since 1970, Franco Harris, Clinton Portis, Maurice Jones-Drew, Adrian Peterson, and Rawls are the only rookie running backs with 800+ rushing yards and to average 5.5+ yards per carry.

Oh, and take a look at the list of rookie running backs with a 200+ yard rushing game:

A number of these stats are highly correlated, so it’s not surprising to see Rawls pop up at the top of many stats. According to the AP voters, he was neither the best rookie runnning back in the NFC West nor the best offensive rookie on Seattle! A broken ankle ended Rawls’ season early, robbing us of a larger sample size to better understand his season. But regardless, it was one of the more uniquely impressive rookie running back seasons, given his undrafted status, high success rate, and league-leading YPC average.