Last season, Fantasy owners were wowed by an impressive rookie class of starting pitchers. Once the establsihed aces and near-aces went off the boards in drafts this spring, owners tended to dip into the pool of sensational sophomores. (Jose Fernandez, who already proved his worth as an ace is a notable -- and positive -- exception.) Many of us now find ourselves relying on the likes of Julio Teheran, Gerrit Cole, Michael Wacha, Tony Cingrani, Shelby Miller, Sonny Gray, Danny Salazar, Alex Wood and Zack Wheeler to fill out prominent spots in our Fantasy rotations.

The relatively high draft picks invested in these young pitchers reflect the high hopes we have for them, based in the assumption that they can only get better. Yet in reviewing the previous two rookie pitcher classes, that optimism may be unfounded or at least premature.

Here are the starting pitchers who were rookies in 2011 and pitched at least 100 innings and posted a sub-4.00 ERA.

Jeremy Hellickson
Michael Pineda
Alexi Ogando
Ivan Nova
Josh Collmenter
Brandon Beachy
Cory Luebke
Vance Worley
Guillermo Moscoso

Injuries have taken their toll on this crew, and Hellickson, Worley and Moscoso failed to live up to their initial success.

The 2012 class of rookie pitchers who met the same benchmarks has had more success, but it features its share of clunkers as well.

Yu Darvish
Hisashi Iwakuma
Jarrod Parker
Matt Moore
Lance Lynn
Wade Miley
Lucas Harrell
Tommy Milone
Scott Diamond
Jose Quintana
Mike Fiers
Joe Kelly
Miguel Gonzalez

Most of the disappointments in this cohort were pitchers who didn't have a high profile as prospects (e.g., Harrell, Milone, Diamond, Fiers), though Moore stands out as one whose performance didn't quite match the hype surrounding him a year ago.

The two lists don't really tell us anything about what to expect from the Class of '13, but it does remind us that, even with elite pitching prospects, there are no sure things.