Welcome to Around The NFL's "Rookie Watch" series, a week-by-week journey ranking this year's promising collection of first-year players.
Between now and the end of the regular season, we'll chart this year's rookie class in an effort to predict which first-year players have the best chance at long careers in our nation's finest sport.
Now let's look at this year's crop of undrafted rookies making an early impact:
Diamonds in the rough
Branden Oliver, Chargers running back: When Around The NFL spoke with Keenan Allen in July, the Chargers wideout called Oliver the most impressive young player at training camp. After turning heads in the preseason, the undrafted rookie out of Buffalo was barely used over San Diego's first four games of the season. That changed Sunday, as Oliver blasted through the Jets for 114 yards on the ground. His 182 total yards from scrimmage were the most by a Chargers back since LaDainian Tomlinson in 2007 -- and more than Gang Green gained all day in the 31-0 loss.
Drawing obvious comparisons to another No. 43 from Chargers lore -- Darren Sproles -- the 5-foot-7, 208-pound Oliver is actually an inch taller than the Eagles back and almost 18 pounds heavier. Game Rewind shows off Oliver's burst and ability to stay on his feet after contact. We saw him bounce off a would-be tackle in space on a short screen pass from Philip Rivers while displaying wiggle through the line both as an outside runner and up the gut.
Isaiah Crowell, Browns running back: We featured Crowell two weeks ago when we tabbed him as the league's top rookie running back coming out of Week 3. Crowell's carries dried up Sunday with Ben Tate back in the mix, but we continue to see the hammer-dropping runner as Cleveland's top long-term talent in a stocked backfield. It's encouraging for Browns fans that Ray Farmer was the only general manager in the NFL who called Crowell personally after the draft.
Allen Hurns, Jaguars wide receiver: The best news for Hurns is that Blake Bortles has the requisite arm strength and big-play mentality to make the most of the rookie's speed. It's been a boom-or-bust campaign for Hurns, who blew the doors off Philly in the opener with 110 yards and twoscores. He caught just four of his 11 targets against the Steelerson Sunday, though, with three drops along the way. Still, he's been a nice surprise for this injury-riddled receiving corps.
Thrust into action
James Hurst, Ravens left tackle: With Eugene Monroe sidelined by knee surgery, Hurst has taken over Baltimore's starting left tackle spot over the past two weeks. After holding his own against the Panthers, the North Carolina product was taken to town against Bjoern Werner and the Coltson Sunday, giving up three sacks, one hit and three hurries. The Ravens, though, continue to praise his veteran-like work ethic.
Taylor Gabriel, Browns wide receiver: Averaging 40 snaps a game, Gabriel has helped plug Cleveland's Josh Gordon-sized void with an 18.4 yards per catch average off 11 grabs. He's been a big-play target for Brian Hoyer over the past two games with a 70-yard catch against the Ravens and a key 49-yarder in Sunday's record-setting comeback against the Titans. He's accounted for more catches and yards than tight end Jordan Cameron this season.
Darrin Reaves, Panthers running back: Stepping into the spotlight following injuries to DeAngelo Williams and Jonathan Stewart, Reaves has averaged 45.5 snaps over the past two weeks. Coaches thought his summertime production was better than Kenjon Barner's, while Game Rewind suggests a fluid runner. He still needs work, but Reaves showed moments of chemistry as a target out of the backfield for Cam Newton.
Philly Brown, Panthers wide receiver: Brown has been used both as a pass-catcher and out of the backfield on a smattering of jet sweeps and reverses for Carolina. Against the Bears, he showed off his 4.45 wheels on a punt return that saw Brown pick the ball off the grass and race 79 yards to the house. He also lost the ball not once -- but twice -- on a momentum-crushing kick return against the Steelers, but his explosiveness keeps coaches coming back for more:
Ryan Hewitt, Bengals tight end/H-back: With Tyler Eifert sidelined by an elbow injury, Hewitt saw his snaps increase weekly prior to Sunday night's wipeout against the Patriots. Serving both as a fullback and tight end, the former Stanford Cardinal has shown well as a blocker, especially in two-tight end sets for the run-heavy Bengals).
K'Waun Williams, Browns cornerback: Stepping in Sunday for struggling first-round cornerback Justin Gilbert, Williams played 36 of 68 snaps against the Titans and made his presence felt with a game-saving, fourth-quarter sack of Charlie Whitehurst with 19 seconds left. Undrafted out of Pittsburgh, Williams earned the highest grade among any Browns defender in the win over Tennessee, per Pro Football Focus.