10 non-first-round picks that excelled in their 2015 rookie seasons

Last week, we took a look back at the first round of the 2015 draft, comparing how each player graded in their final year in college to how they graded as rookies in the NFL. Today, we're going to take a look at the second round and beyond, highlighting 10 players who graded well in college and carried that on into their rookie year in the NFL.

1. Tyler Lockett, WR, Seattle Seahawks

Round 3, pick No. 69

2014 PFF College grade: +33.7 (highest-graded WR in class)

2015 PFF NFL grade: +6.8 (26th-highest-graded WR in NFL)

While Lockett was also a very good returner in 2015, scoring on both a punt and kick return as a rookie, he really impressed as a wide receiver. Scoring six touchdowns in the regular season, he made defenders miss when he had the ball in his hands, forcing eight missed tackles on 51 receptions.

2. Henry Anderson, DE, Indianapolis Colts

Round 3, pick No. 93

2014 PFF College grade: +60.1 (highest-graded interior defender in class)

2015 PFF NFL grade: +12.6 (14th-highest-graded interior defender in NFL)

Injury cut short Anderson's impressive rookie campaign, with the former Stanford defender producing a sack, three hits, and 18 hurries as a pass-rusher. He was even better against the run, making a tackle that resulted in a defensive stop on 12.0 percent of his run-defense snaps, the second-highest percentage of any 3-4 defensive end in the league.

3. Stefon Diggs, WR, Minnesota Vikings

Round 5, pick No. 146

2014 PFF College grade: +11.3 (23rd-highest-graded WR in class)

2015 PFF NFL grade: +6.1 (32nd-highest-graded WR in NFL)

We actually underrated Diggs coming out, with his 2014 college grade leading us to not expect too much from him as a rookie. He delivered in the NFL, though, forcing 13 missed tackles from 52 receptions and dropping just two of the 54 catchable passes thrown his way.

4. Ronald Darby, CB, Buffalo Bills

Round 2, pick No. 50

2014 PFF College grade: +9.2 (32nd-highest-graded CB in class)

2015 PFF NFL grade: +13.2 (ninth-highest-graded CB in NFL)

Darby is another guy that we clearly weren't high enough on heading into the draft. He far exceeded our expectations, finishing the year with the ninth-highest coverage grade of all cornerbacks in the NFL, taking home PFF's Defensive Rookie of the Year honor. He allowed a completion on just 54.3 percent of the passes thrown into his coverage, and recorded two interceptions and 13 pass breakups.

5. Duke Johnson, RB, Cleveland Browns

Round 3, pick No. 77

2014 PFF College grade: +18.9 (fourth-highest-graded RB in class)

2015 PFF NFL grade: +5.0 (23rd-highest-graded RB in NFL)

While undrafted free agent rookie Thomas Rawls (sixth-highest-graded RB in the class) was the better runner in 2015, Duke Johnson had the fifth-best receiving grade of any running back in the NFL. He caught 61 passes and forced 26 missed tackles on those receptions, which should give Browns fans cause for optimism in 2016.

6. Markus Golden, OLB, Arizona Cardinals

Round 2, pick No. 58

2014 PFF College grade: +46.1 (third-highest-graded edge defender in class)

2015 PFF NFL grade: +5.2 (48th-highest-graded edge defender in NFL)

He was inconsistent as a pass-rusher as a rookie, but Golden still managed to rack up seven sacks, nine hits, and 35 hurries. At 12.5, he finished the year with the sixth-best pass-rushing productivity rating of any 3-4 outside linebacker in the NFL.

7. Grady Jarrett, DT, Atlanta Falcons

Round 5, pick No. 137

2014 PFF College grade: +53.4 (second-highest-graded interior defender in class)

2015 PFF NFL grade: +11.3 (31st-highest-graded interior defender in NFL)

Jarrett played just 268 snaps as a rookie, but made the most of them with a strong performance against the run. With 14 tackles resulting in a defensive stop from his 113 snaps against the run, he had the fourth-best run-stop percentage of any defensive tackle in the league, at 12.4 percent.

8. Quinten Rollins, CB, Green Bay Packers

Round 2, pick No. 62

2014 PFF College grade: +24.8 (fourth-highest-graded CB in class)

2015 PFF NFL grade: +7.7 (22nd-highest-graded CB in NFL)

Rollins graded positively in coverage, against the run, and even chipped in with a sack and two hurries as a pass-rusher in his rookie season. Targeted 39 times in coverage, he gave up 22 receptions, but didn't allow a touchdown and came away with two interceptions and five pass breakups.

9. Quandre Diggs, CB, Detroit Lions

Round 6, pick No. 200

2014 PFF College grade: +17.8 (eighth-highest-graded CB in class)

2015 PFF NFL grade: +6.3 (26th-highest-graded CB in NFL)

Like Rollins, Diggs graded positively both in coverage and against the run. He gave up a little more through the air than Rollins, with 33 receptions and three touchdowns from 53 throws into his coverage, but he did break up four passes.

10. Adrian Amos, S, Chicago Bears

Round 5, pick No. 142

2014 PFF College grade: +15.7 (eighth-highest-graded safety in class)

2015 PFF NFL grade: +5.2 (22nd-highest-graded safety in NFL)

Amos had a negative coverage grade in his first year in the NFL, and his 10 missed tackles were tied for 32nd-most amongst safeties, but he did grade well against the run. At +4.8, only 10 safeties in the NFL had a higher grade in run defense in 2015.