Bed check: Wrapping up Day 4

Eye On The Line (1:10)

ESPNBoston's Mike Reiss reports from Patriots training camp examining their pass rush. (1:10)

FOXBOROUGH, Mass. -- Wrapping up the fourth day of training camp and the key storylines:

Second day of full-pads practice. Bill Belichick attempts to create stressful situations in training camp to test his players, and this practice was one of them. The Patriots had been in full pads on Saturday and were in them again Sunday, challenging them physically. Some injury situations have cropped up, with defensive end Rob Ninkovich, linebacker Tracy White, tight end Visanthe Shiancoe and offensive lineman Jamey Richard all banged up or held out. Rookie cornerback Alfonzo Dennard (hamstring) has remained out since Friday.

Hightower's powerful presence is felt. Rookie linebacker Dont'a Hightower brought the force in the linebacker vs. running backs blitz pick-up drill, colliding with fullback Eric Kettani and knocking him back into running backs coach Ivan Fears. Powerful stuff. Hightower is listed at 6-foot-3 and 270 pounds. The Patriots haven't had many defenders with that profile and he looks like he's going to help immediately.

Ridley and the running backs. The potential makeup of the running backs corps was a hot topic for media members after practice, with Stevan Ridley and Shane Vereen stopping to speak with reporters. Ridley said it's any young kid's dream to be the No. 1 option.

Sirius NFL Radio is in the house. Sirius XM NFL Radio's Pat Kirwan and Tim Ryan, who co-host the "Movin' the Chains" program, broadcast live from noon-4 p.m. ET. There was a lot to digest for Patriots fans, with cornerback Devin McCourty, left tackle Nate Solder, safety Patrick Chung, coach Bill Belichick, director of player personnel Nick Caserio, owner Robert Kraft and quarterback Tom Brady interviewed.

Star performer of the day. Tom Brady-to-Brandon Lloyd. The quarterback-to-receiver connection hooked up for two touchdowns, the first a long bomb that electrified the crowd of 14,000.

Tough day at the office. Rob Gronkowski. Tight end has two uncharacteristic drops, one of which is turned into an interception, the other coming at the goal line.

Storyline to monitor. After Monday's players day off, might any players on the physically unable to perform list return to practice?

Rookie watch. First-round draft choice Chandler Jones received a lot of action at right defensive end with Ninkovich limited. ... Free agent defensive end Justin Francis (Rutgers), who was carted off with cramping on Saturday, returned and continued to show up with some playmaking ability. ... Sixth-round draft choice Nate Ebner, the safety/special teamer from Ohio State, has yet to practice.