The final phase of offseason workouts, a three-day mandatory minicamp, kicked off on Tuesday, and Seahawks coach Pete Carroll is really excited not only about what he saw Tuesday, but what has taken place throughout offseason workouts.

"We had really good work today to start it off," Carroll said. "I see nothing but good things. I'm really fired up our opportunities to see some of the young guys—we're moving into where you can see them play with veteran players. We just made a lot of progress, so it's just been a really good offseason for us. Hopefully we'll get two more great days in and wrap this thing up."

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Here are five takeaways from Tuesday's practice and Carroll's press conference that followed.

1. The Seahawks like homegrown cornerbacks.

The Seahawks have been able to repeatedly turn late-round cornerback picks into starters—and in the case of Richard Sherman, an All-Pro—not just because they have an eye for talent, but also because of the way Carroll, Kris Richard and Rocky Seto have been able to teach those players Seattle's system. It doesn't always come easily or quickly—even Sherman began his rookie season third on the depth chart at left corner—but given time to learn Seattle's techniques and principles, players like Byron Maxwell, Jeremy Lane and DeShawn Shead have become quality starters by developing in the only NFL system they have ever known.

"I like that," Carroll said. "I like guys who have not been coached by anybody else, I like that we've only filled their heads with our thoughts. I do like that. We can transition guys and teach them and all that, but if you can make it a pure process of our stuff—we're very strict about how we do this, very disciplined, we've spent 20 years putting this stuff together, so we really have a deep belief in it—when we can really insert the thoughts and ideas and principles of it, guys can make quick progress with it."

The Seahawks haven't relied entirely on homegrown cornerbacks, and at times that has worked out very well (Brandon Browner) and at other times it hasn't (Cary Williams), but for the most part Seattle has had success at cornerback by developing young players from early in their careers.  

"Shead is a really good example," Carroll said of the former undrafted free agent who has played multiple positions in Seattle's secondary. "DeShawn has really come along. What a great story for us in our program. He has played safety and corner, and he's doing a really nice job at the line of scrimmage. He has had a fantastic offseason this year, the best by far he has ever had."

2. Carroll is excited to have Chris Clemons back.

Defensive end Chris Clemons, who re-signed with Seattle this offseason after two years in Jacksonville, was on the field Tuesday after staying away for most of Seattle's voluntary workouts. While it's far too soon to know exactly where Clemons will fit into the defensive line rotation, Carroll sees a lot of value in the player who was a starter in Seattle from 2010 to 2013, both as a talented pass-rusher and as an experienced veteran who can help younger players.   

"Clem's a really, really savvy football player," Carroll said. "I'm hoping that he's going to add a lot to our guys. I don't think that Frank (Clark) could get a better guy to learn from and to watch. The kinds of things that Clem did our program we're still looking for in our program now. I'm hoping he'll be a big factor for us. He's got to get in shape, be ready and all that stuff. It's going to be a while before we can tell how he can fit in, but he has a lot of great qualities about him, and we love having back on the team."

3. The battle at strongside linebacker is "really wide open."

With Bruce Irvin leaving in free agency, the Seahawks have an opening in their base defense at strongside linebacker, and as of now, that competition could go a number of different directions.

"It's wide open," Carroll said. "It's really wide open. You can't call it right now. We won't call that until after we're playing (preseason) games."

Among the candidates for the job are Mike Morgan, a veteran who, between his college and NFL careers, has played for Carroll for nine of the past 10 years, converted defensive end Cassius Marsh, converted defensive back Eric Pinkins, and Kevin Pierre-Louis, who up to this point has primarily played weakside linebacker.

"Mike Morgan gives us the stability, he's been in the position for 18 years now," Carroll said, exaggerating slightly. "Cassius has done a really nice job picking up the position. Pinkins has done a really good job, he gives us a superior athlete at the spot, he's so fast and all coming from the DB spot. So we've got a nice variety. We also played Kevin Pierre-Louis there through the second half of OTAs to see what he would do as well, so we know where we can plug him in if we need to. He looks very good there also. So it's a really good spot, it'll be fun to watch in camp. The preseason games will be enormous for that."

4. Rookie TE Nick Vannett "has surprised us" as a pass-catcher.

With Kasen Williams once again having a standout practice, Carroll talked about receiver depth and noted, "It's gonna be a big battle at receiver." But it isn't just the wide receivers turning heads with their pass-catching ability. In particular, rookie tight end Nick Vannett has impressed in that department, especially considering that the Seahawks mostly talked about using him as a blocking tight end when they drafted him in the third round.

Until the Seahawks put on pads in training camp, Vannett won't be able to really show off his blocking ability, but he has made a strong early impression with his ability as a pass-catcher.  

"Wow, he has surprised us," Carroll said. "He has surprised us. We knew he could catch the ball and all of that, but he's a very natural catcher. He shows the savvy and the instincts that you hope a guy would have. I know Russell (Wilson) has really clicked into him, he picked up on it and has already shown trust working the ball his way. He exceeded our expectations a little bit in a positive, great way."

5. The Seahawks are "really encouraged" by what they've seen from rookie D-lineman Quinton Jefferson.

With Michael Bennett sidelined by a sore ankle, fifth-round pick Quinton Jefferson saw some snaps with the starting defense Tuesday, another sign of progress for the rookie out of Maryland. Comparing Jefferson to a Pro Bowler like Bennett would be unfair to a rookie who has yet to participate in training camp, let alone an NFL game, but Jefferson has shown early on two traits that helped Bennett become a standout defensive lineman: effort and versatility.

"He's done a really nice job," Carroll said. "What really jumps out about Quinton is that he's got such a great motor. He really plays hard… He's shown the versatility to play a number of spots. He has played Michael's spot, and also 3-techique in third-down stuff too. We're really encouraged by what we've seen and anxious to see him in pads when the time comes."