A fourth-round rookie, Pierce didn't take long to make his mark once training camp kicked off. The Florida product flashed between the tackles with tough running and cutback ability. Pierce is on a trajectory that could make him the star of the preseason. 

It's early, but Pickens looks like the latest WR prospect to come through the Steelers' pipeline. With Pittsburgh's track record and Pickens' raw talent, the second-rounder is ready to make his name known.

Jackson showed off an impressive backflip before practice last week, and his play on the field should have the 49ers' front office doing cartwheels. The former USC pass-rusher turned heads in training camp and will look to impress under the national spotlight once preseason starts.

It takes a lot to earn praise from a star quarterback like Aaron Rodgers, especially for rookies - but that's exactly what Doubs has done this offseason. In a young receiver group eager to make up for the loss of Davante Adams, Doubs has risen to the challenge.