Redskins.com's Jake Kring-Schreifels and Andre Earls break down the key plays and highlights from Day 4 of the Washington Redskins' 2018 training camp in Richmond, Va.

Defense:

-- What started out as a rather calm fourth day of practice, considering the team wore full pads for the first time in training camp, ended loudly. During a red zone period in the second half of the morning, things got a little chippy between safety Montae Nicholson and running back Byron Marshall, which prompted the defense's captain and megaphone, D.J. Swearinger, to begin consistently barking for the rest of practice. Quarterback Alex Smith pitched the ball to Marshall around the 10-yard line and Nichcolson took a good angle in what would have been a close play in the front corner of the end zone. The two started jawing back into their huddles. That amped up the proceedings considerably, turning the final team drill with the third unit considerably more intense.

-- It even inspired linebacker Zach Brown to amp up his own vocal encouragement for the linebackers unit before camp broke until Tuesday. He kept yelling at inside linebacker Jerod Fernandez to keep the intensity high and wrap up opponents, and the defense wasn't shy about hitting a little harder than what they'd previously shown an hour earlier, when they had 1-on-1 hitting drills.

-- On the first play from scrimmage, linebacker Mason Foster went down and trainers tended to him on the side. He quickly got back up and watched practice with his teammates for the rest of the session, though no medical update was given at the conclusion of practice.

-- Throughout the first few days of camp, cornerback Orlando Scandrick has primarily started practice playing on the outside and then shifted to the slot position in later team periods. On Sunday, he shifted to the slot after a couple of early snaps and cornerback Quinton Dunbar took over his spot. In 1-on-1 drills inside the 10-yard line, he prevented three passes from being caught, the most impressive of which took place on a slant route to wide receiver Jamison Crowder. On another red zone drill, he broke up a pass to wide receiver Josh Doctson. His biggest challenge will be limiting his physicality as plays develop, though he seems to be refining his technique well so far.

-- The outside linebackers unit was without Ryan Anderson once again as he recovers from back spasms. Pernell McPhee seems to be a useful addition in his wake, often playing opposite of Anderson, and setting the edge against the run. He helped contribute knocking down running back Derrius Guice on a blitz call, and for one play took over the Mike position in a nickel package in the red zone, snapping the huddle.

-- It's also easy to forget about linebacker Ryan Kerrigan thanks to his consistent play. One snap caught my attention when Kerrigan sped off the line a half second before any other defensive lineman and crunched the pocket accordingly. During 1-on-1's he also put some nice moves on Morgan Moses, who is still working back day by day.

-- Jake Kring-Schreifels

Offense:

-- A major standout Sunday was high priority wide-out Paul Richardson Jr. Whether it was 1-on-1, 7-on-7, or 11-on-11 drills, he was having a day, beating anyone who lined up against him. In particular, he had a major catch against safety Montae Nicholson during red-zone drills in the back of the end zone on a ball thrown into tight coverage.

-- In general, the offense won the day. During 11-on-11 drills, the defense was getting beaten more than it would've liked to. A perfect example of this was a wide open throw from quarterback Alex Smith to wide receiver Josh Doctson, who proceeded to slam dunk the football through the goalpost. Smith also completed a corner ball to Vernon Davis that was definitely worth a rewind.

-- Throughout the day, it seemed as though Smith was giving Jamison Crowder considerable attention, and it's clear the two were working on timing due to the high volume of targets that he was receiving. They connected a lot, and after some plays, Smith would go to Crowder and dissect what happened.

-- It should be noted that running back Rob Kelley got some first team reps early during 11-on-11 drills. With Derrius Guice and others in the mix, first team reps for Kelley haven't been as plentiful. As training camp progresses, it's becoming clear that head coach Jay Gruden and running backs coach Randy Jordan are looking to evaluate talent and compatibility.

-- Second-year tight end Jeremy Sprinkle also sprinkled in some first team reps (no pun intended), and caught a pass from Smith on a corner route. Vernon Davis mentioned in his presser the other day that Sprinkle was coming along well and continues to be extremely observant. We're now starting to see that manifest.

-- The second and third teams also didn't disappoint. Two scrappy undrafted free agents, tight end Matt Flanagan and linebacker Vontae Diggs, had a small altercation after a 7-on-7 play with the third team. It was quickly broken up, but it predicted how the rest of practice might be with the full pads on.

-- Quarterback Colt McCoy was his usual self, but he seems to be fine-tuning the little things. Today, it was his cadence -- he drew a few offsides penalties from the defensive line. Meanwhile, for the past few days of camp, third string quarterback Kevin Hogan has been staying after practice for 30 to 45 minutes consistently, and we're starting to see his extra efforts turn into some solid plays during team drills. Today, he had an increased polish on his ball, and one long ball on a post-route to wide receiver Cam Sims was particularly noteworthy.

-- One medical note: wide receiver Brian Quick didn't participate in practice due to a thigh contusion. He was seen early in the morning on the bike while team stretches were happening. Up until this point, he's had a strong camp, and his minor injury lists him as day-to-day. The team will take an off day on Monday and be back to practice Tuesday morning.

-- Andre Earls

Special Teams:

-- After getting more physical on working on punt returns with the pads on, Dustin Hopkins closed out practice making 3-of-5 field goals.