Those in dynasty leagues may already be thinking about their rookie drafts, which for many occur just a week or so after the NFL Draft is complete. Before looking ahead, it's often prudent to take a quick look back, and learn from the mistakes of yesterday -- so as not to make them again.

I think a key lesson from last year is that trading up to get one of the elite, most highly regarded prospects isn't always the way to go. Sometimes trading down and getting more picks and more bites from the apple is best -- just like in the actual NFL.

Here's how things went in my dynasty league rookie draft last May. (Veteran players, also available to be drafted, have been removed.)

PickPlayerPos
1.01Leonard Fournette, Jac.RB
1.02Corey Davis, Tenn.WR
1.03Christian McCaffrey, Car.RB
1.04Joe Mixon, Cin.RB
1.05Dalvin Cook, Minn.RB

These were the top picks in most rookie drafts a year ago. Despite Cook coming off an ACL injury, it's possible he'd be the top pick if teams had a do-over. Fournette certainly had a great rookie season, as did McCaffrey. Davis showed promising signs in the playoffs. Mixon? Well, he had a disappointing first season. I don't think he'd be selected this high again.

PickPlayerPos
1.06O.J. Howard, T.B.TE
1.07Mike Williams, LACWR
1.08John Ross, Cin.WR
1.09David Njoku, Clev.TE
1.10Evan Engram, NYGTE
1.11Alvin Kamara, N.O.RB
1.12Zay Jones, Buff.WR

That's right: If you had the 10th or 11th pick in this 12-team draft, you could have drafted Evan Engram or rookie of the year Alvin Kamara. Needless to say, Kamara would be selected in the top 2 or 3 picks of every rookie draft, knowing what we know now. No need to trade up to select him. It might be too soon to call Ross or Jones wasted picks, but let's just say early returns aren't good.

PickPlayerPos
2.01Samaje Perine, Wash.RB
2.02D'Onta Foreman, Hou.RB
2.03JuJu Smith-Schuster, Pitt.WR
2.04Curtis Samuel, Car.WR
2.05Kareem Hunt, K.C.RB
2.06Chris Godwin, T.B.WR
2.07Joe Williams, S.F.RB
2.08James Conner, Pitt.RB
2.09Adam Shaheen, Chi.TE
2.10Deshaun Watson, Hou.QB
2.11Cooper Kupp, LARWR
2.12Bucky Hodges, Minn.TE

Smith-Schuster, Hunt, Watson and Kupp would all be selected in the top 10 picks if there were a do-over. Watson, ACL injury and all, might only be selected behind a couple of the running backs. All four should be fairly early picks in fantasy leagues this season. Nobody would be particularly surprised if at least a couple go on to have better careers than any of the first-round rookies.

PickPlayerPos
3.01Patrick Mahomes, K.C.QB
3.02Marlon Mack, Ind.RB
3.03Gerald Everett, LARTE
3.04Josh Reynolds, LARWR
3.05Carlos Henderson, Den.WR
3.06Wayne Gallman, NYGRB
3.07Jeremy McNichols, T.B.RB
3.10Jonnu Smith, Tenn.TE
3.11Jamaal Williams, G.B.RB
3.12ArDarius Stewart, NYJWR

Things aren't quite as pretty in the third round, but Mahomes, Gallman and Williams are all potential NFL and fantasy starters this season (especially Mahomes, who will be behind center in Week 1). More players you could have had on your fantasy teams without trading up.