Robert Turbin turned the corner and took off down the sideline, showing impressive speed on one of the longest runs of the day. Then, for good measure just as the play was ending, the fourth-year running back dropped a shoulder and knocked an unsuspecting defensive back off of his feet. That and more in today's version of Seahawks training camp observations:

1. Turbo's hip is fine

Turbin missed offseason workouts while recovering from hip surgery, and was eased back into action the first couple of days of camp, but fours day in, it's clear that the player known as Turbo is functioning at full speed. On the play mentioned above, and several other nice runs, Turbin showed impressive burst, and thanks to the Seahawks now being in pads, the 222-pound back was also more than willing to initiate some contact.

Turbin's three-year career has been a bit overshadowed by the presence of Marshawn Lynch, one of the NFL's best backs, but his contributions to Seattle's offense have been big. After being banged up at times last season, Turbin looks healthy and fast, and should again be an important part of the offense, not just as Lynch's backup, but as a third-down back and lead back in the two-minute offense.

2. Seisay looks the part

One practice is way, way too small of a sample size to judge a player, so we don't yet know how Mohammed Seisay will do in Seattle, but what was evident in the cornerback's first practice with his new team is that Seisay certainly looks like a Seahawks cornerback. Seisay, who came to Seattle in a trade with Detroit on Sunday, measures 6-foot-2, 202 pounds, and perhaps more significantly for a Seahawks corner, has very long arms. As you might expect for a new cornerback, Seisay got beat a few time in practice, but also used those long arms to break up a couple of passes. As has become the custom for a cornerback new to Seattle, Seisay was coached-up not only by his actual coaches, but by Richard Sherman, who goes out of his way to help young or newly-acquired players learn Seattle's coverage techniques.

 "I think you can see the fantastic athlete that he is," defensive coordinator Kris Richard said. "It never hurts to have another long, tall, fast corner on the field ready to compete. The door is wide open in regards to competition, everybody understands that, and knows we're going to put the best players out there on the football field to compete for our team. He's going to be a good addition for us… He did a really good job in his first practice out there. It was positive, we threw him out there on the fly and he executed, he had some good plays out there."

3. The D-line depth is showing

When the Seahawks finished out the 2014 season, depth was a serious concern on the defensive line thanks to a number of injuries. Yet thanks to players returning to health, as well as a few additions, the Seahawks look very deep and talented on the line. Not only are the players you'd expect to shine making big plays—Michael Bennett was constantly in the backfield, particularly against the run—but some less familiar faces are sanding out as well. Cassius Marsh, who has been a bright spot early in camp, saw a lot of action for the first time with Cliff Avril sitting out Monday, and the second-year end continued to impress. Rookie Frank Clark had one of the best defensive plays of the day, blowing through the line of scrimmage and putting a solid hit on fellow rookie Rod Smith just as the running back took a handoff, and free-agent addition Ahtyba Rubin, who is now one of the leading candidates to start at defensive tackle following Tony McDaniels' release, is earning nothing but praise from his coaches.

"Ahtyba Rubin has been doing a fantastic job," Richard said. "He is a big, massive, strong man in there. He is absolutely going to fill the role we need as a big body in there taking on the run."

Emptying out the notebook:

• Rookie Kristjan Sokoli, who had been working at center up to this point, saw significant playing time at left guard with the first-team offense. It's way too early to make any judgements on that, but that could be a sign that the Seahawks want to see what the former defensive tackle can do at a different position, and perhaps also that there is indeed a competition for the vacancy at left guard after Alvin Bailey saw all the first-team action at that spot in offseason workouts and in camp up to this point. 
• This is hardly breaking news, but tight end Jimmy Graham had yet another impressive catch, this one a leaping touchdown grab in traffic, which he punctuated with a leaping spike.
• Undrafted rookie Triston Wade, who is listed as a safety on the roster, made a couple of nice plays while lining up at cornerback, twice breaking up long passes down the sideline.
• Kevin Pierre-Louis' speed really stands out on the practice field, and on Monday that included a blitz while playing in the nickel package. It was impressive how quickly Pierre-Louis went from being a few yards off the line of scrimmage to being in the backfield untouched.
• Brock Coyle is apparently a compassionate linebacker. On one play, rookie Tyler Lockett caught a short pass over the middle of the field and was on a collision course with Coyle, whom he did not see. Rather than hammer the rookie, which is very much frowned upon, or even give him a half-speed hit, Coyle simply put his hands in the air and absorbed the blow with his chest.
• Seventh-round pick Ryan Murphy continues to find himself around the ball early in the training camp. On Monday, the safety from Oregon State had an interception with a long return, and he nearly intercepted another pass in the end zone.
• On the last play from scrimmage, Chris Matthews made something beautiful out of a play that started off very ugly. First a defensive lineman jumped offside, then it appeared there was a false start, though the whistle wasn't blown. Amidst the confusion, the snap ended up on the ground, but R.J. Archer picked it up heaved a pass into the end zone. After all of that sloppiness, however, Matthews made a great adjustment on an underthrown ball and made a nice catch in the end zone.