Not every fantasy football league starts fresh every summer. There are some, such as keeper or dynasty leagues, which allow owners to keep a set number of players from one year to the next, putting younger players with upside at a premium compared to older veterans whose careers are on the downswing.

To determine which players should be prioritized as potential keepers in this year’s draft, each player’s projected 2019 fantasy football production was compared to the replacement level at his position and then adjusted for how many years the player has before hitting the end of his peak. Peak ages used were: quarterbacks (30 years old), running backs (25), wide receivers (29) and tight ends (28). The list also reflects the projected future outlook for the players and their teams.

Some leagues don’t allow first-round picks to be kept, but this list ranks every 2019 keeper prospect.

1. Saquon Barkley (NYG-RB, 22 years old)

Barkley was one of the lone bright spots for the New York Giants last year, rushing for 1,307 yards (second most in NFL) and 11 touchdowns on 261 carries. He caught 91 of 121 passes thrown his way, too, for an additional 721 yards and four touchdowns. Barkley’s league-leading 2,028 yards from scrimmage were the third most from a rookie in NFL history, and his 91 receptions also set a record for most by a rookie running back.

If Barkley continues to get the lion’s share of his team’s touches (48 percent in 2018), he will be a fantasy stud for years to come.

2. Christian McCaffrey (CAR-RB, 23 years old)

McCaffrey didn’t get as big a share of his team’s touches (41 percent) as Barkley, but he did join Barkley as the only running backs to exceed 1,000 yards rushing and 700 yards receiving in 2018. McCaffrey is also one of three running backs since 2002, when the league expanded to 32 teams, to record at least 100 catches in a season.

3. DeAndre Hopkins (HOU-WR, 27 years old)

Since his rookie year in 2013, only Antonio Brown has earned a higher share of his team’s passing targets than Hopkins. Over the past two seasons, Hopkins recorded the highest (34 percent in 2017) and third-highest (33 percent in 2018) share of targets among all wide receivers.

Hopkins also gets a third of his team’s red-zone looks, nearly triple that of his closest teammate, former Texans tight end Stephen Anderson (13 percent from 2017 to 2018), who is now with the New England Patriots.

4. Alvin Kamara (NO-RB, 24 years old)

Kamara burst on the scene in 2017, touching the ball 201 times for 1,554 yards from scrimmage and 13 total touchdowns. He followed that up with 275 touches, 1,592 yards from scrimmage and 18 total touchdowns in 2018. Now that his running-back-by-committee colleague for those two years, Mark Ingram, is with the Baltimore Ravens, Kamara should earn even more opportunities in 2019, and that means more fantasy points.

Over the past two seasons, no running back has produced more fantasy points per opportunity (with a minimum of 200 rushes plus targets) than Kamara.

5. Odell Beckham Jr. (CLE-WR, 26 years old)

For five years, Beckham was a mainstay in the Giants passing offense. The first-round pick from 2014 caught 390 passes for Big Blue, resulting in 5,476 yards and 44 touchdowns. Unhappy with his situation in New York, Beckham was shipped off to the Cleveland Browns, joining a nucleus of quarterback Baker Mayfield and running back Nick Chubb to form the class of the AFC North.

The upgrade at quarterback from an aging Eli Manning to Mayfield should result in a boost for Beckham. Mayfield had a higher passer rating than Manning last year and was also graded higher by ESPN’s Total Quarterback Rating. Football Outsiders also recorded a significant discrepancy between the two, listing Mayfield as the 12th most valuable passer of 2018 and Manning 22nd, per their Defense-adjusted Yards Above Replacement metric.

6. Ezekiel Elliott (DAL-RB, 24 years old)

7. Davante Adams (GB-WR, 26 years old)

8. JuJu Smith-Schuster (PIT-WR, 22 years old)

9. Michael Thomas (NO-WR, 26 years old)

10. Mike Evans (TB-WR, 26 years old)

11. Joe Mixon (CIN-RB, 23 years old)

12. Nick Chubb (CLE-RB, 23 years old)

13. Julio Jones (ATL-WR, 30 years old)

14. Dalvin Cook (MIN-RB, 24 years old)

15. Stefon Diggs (MIN-WR, 25 years old)

16. Travis Kelce (KC-TE, 29 years old)

17. David Johnson (ARI-RB, 27 years old)

18. Amari Cooper (DAL-WR, 25 years old)

19. Melvin Gordon (LAC-RB, 26 years old)

20. George Kittle (SF-TE, 25 years old)

21. Keenan Allen (LAC-WR, 27 years old)

22. Kerryon Johnson (DET-RB, 22 years old)

23. Le'Veon Bell (NYJ-RB, 27 years old)

24. Tyreek Hill (KC-WR, 25 years old)

25. Antonio Brown (OAK-WR, 31 years old)

26. James Conner (PIT-RB, 24 years old)

27. Patrick Mahomes (KC-QB, 23 years old)

28. Brandin Cooks (LAR-WR, 25 years old)

29. Adam Thielen (MIN-WR, 29 years old)

30. Todd Gurley (LAR-RB, 25 years old)

31. Kenny Golladay (DET-WR, 25 years old)

32. Zach Ertz (PHI-TE, 28 years old)

33. Josh Jacobs (OAK-RB, 21 years old)

34. D.J. Moore (CAR-WR, 22 years old)

35. Leonard Fournette (JAC-RB, 24 years old)

36. Aaron Jones (GB-RB, 24 years old)

37. Chris Godwin (TB-WR, 23 years old)

38. Robert Woods (LAR-WR, 27 years old)

39. T.Y. Hilton (IND-WR, 29 years old)

40. Cooper Kupp (LAR-WR, 26 years old)

41. Sony Michel (NE-RB, 24 years old)

42. Calvin Ridley (ATL-WR, 24 years old)

43. Deshaun Watson (HOU-QB, 23 years old)

44. Mike Williams (LAC-WR, 24 years old)

45. A.J. Green (CIN-WR, 31 years old)

46. Marlon Mack (IND-RB, 23 years old)

47. David Montgomery (CHI-RB, 22 years old)

48. Baker Mayfield (CLE-QB, 24 years old)

49. Miles Sanders (PHI-RB, 22 years old)

50. Derrius Guice (WAS-RB, 22 years old)

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