The Raiders are kicking the tires on former Jets running back Isaiah Crowell, and they're apparently open to having Marshawn Lynch back, if he's so inclined. I've been holding on to Chris Warren in my main dynasty league. Am I wasting my time?

Warren, some may recall, was an undrafted free agent running back who looked very good for Oakland last preseason. Then he suffered a knee injury that got him placed on IR for the season. But Jon Gruden said, "He'll be a guy worth keeping an eye on next year."

Gruden says a lot of things, many of which can be safely ignored. But Warren led the league in rushing last preseason. Does that production mean anything? Warren was undrafted, but flashed some ability in college at Texas and was a combine invite. (Where he proceeded to run a 4.69; hmm.)

I took a look at preseason rushing numbers from the last 10 years. In the table, all running backs who went over 175 yards in August are shown.

PRESEASON RUSHING LEADERS, 2009-2018
YearPlayer Team Att Yds Avg TD
2010Anthony Dixon SF 743004.14
2018Chris Warren OAK 582925.02
2012William Powell ARI 422495.93
2014Lorenzo Taliaferro BAL 652433.71
2010Michael Bennett OAK 542364.40
2011Kendall Hunter SF 352316.61
2013Khiry Robinson NO 492284.70
2016Mack Brown WAS 392275.81
2018Ryan Nall CHI 322237.01
2013Jordan Todman JAC 292237.72
2016Derrick Henry TEN 342166.43
2013Joseph Randle DAL 552153.91
2011Da'Rel Scott NYG 1421315.22
2014Joe Banyard MIN 362125.90
2014Rashad Jennings NYG 352126.11
2012Rashad Jennings JAC 472094.40
2012Nate Eachus KC 342066.11
2013Christine Michael SEA 402015.01
2010Cedric Peerman CIN 312016.53
2016Rob Kelley WAS 381985.21
2018John Kelly LA 461974.33
2018Mike Boone MIN 491954.01
2016Elijhaa Penny ARI 491954.01
2014Andre Williams NYG 381955.12
2012Alfred Morris WAS 391955.01
2011Armond Smith CLE 311926.22
2017Corey Grant JAX 221918.71
2014Jeremy Hill CIN 411904.60
2011Ryan Mathews SD 241877.82
2012Justin Forsett HOU 291856.42
2015Zach Zenner DET 351835.22
2010Jonathan Dwyer PIT 391834.71
2017Cameron Artis-Payne CAR 281806.43
2010Jackie Battle KC 351805.11
2014Fozzy Whittaker CAR 431794.22
2013David Wilson NYG 241797.51
2015Jarryd Hayne SF 251757.00
2011Jonathan Dwyer PIT 371754.71

I see a handful of players from the list who went on to have significant seasons, if not careers. Alfred Morris stands out as a guy who caught our eye in the preseason and went on to have some good years. Another Washington back, Rob Kelley, also had his moments.

There are also some early picks who did well in August and continued when the games counted. Jeremy Hill, Derrick Henry, Ryan Mathews. It happens.

I don't think there's enough there to say Warren is a must-hold in dynasty. And if Oakland does bring back Lynch, or sign Crowell, it will be even tougher for him to make an impact. For now, I'm hanging onto him. But if some other young runner turns my head in August and I need the spot, he might end up back on the wire.

--Andy Richardson