Not much of a factor last season for the Sun Devils, Jarrett has improved his play tremendously, both against the run and in getting pressure on the quarterback.
His spark from the defensive end position with the ability to play inside due to his size has been big for the defense as players have moved in and out of the lineup due to injuries. His play and demeanor have made him a leader on that side of the ball and it hasn't gone unnoticed.
"He has played extremely well," coach Dennis Erickson mentioned. "Right now, defensively, he is playing as well as anybody we have. The great thing about Jamaar is he has stepped up in all aspects of his life, including academics.
"Everything he has done has improved over the last six months. On the field he is playing really well. I am proud of him and he is becoming a leader out there who is stepping up."
Told of these comments, Jarrett was very humble, and said just about everything you would want somebody in leadership position for your football team to say.
"Classroom-wise I don't know if I'm much of a leader," Jarrett said with a smile, "but I'm working on that and getting better. I'm trying to step up as a leader (on the field), we need a leader on defense and that's what I'm trying to do."
From an outside perspective, the team looked lost during the loss to California; a problem that usually falls on the coaches' shoulders. With so many discipline problems and lack of attention to detail this season, it has been easy for Erickson and the coaching staff to take blame, but Jarrett doesn't feel that was the case against Cal.
"I think a lack of energy and focus," Jarrett pointed out. "I don't know exactly what, but I saw a lack of energy. Preparation wasn't a problem in my eyes. I don't think that was a problem at all, we just came out flat, it was 26-3 out of nowhere and I guess people just kind of gave up, and that's just how it went.
"Our bye week, we prepared a lot. The coaches had a good plan for them and I think we really came out flat, I don't believe preparation was a problem, we just came out flat, missed tackles and at halftime some of us just gave up."
When players such as Jarrett make a drastic improvement from one year to the next, it's usually a product of one of two things: getting physically more prepared whether it be stronger or faster, or more often the game becoming easier.
"I've just been watching James (Brooks) and everybody and just taking things down and using it to my advantage with my size," The 6-5 252 Jarrett speculated. "The game slowed down a lot from freshman year."
Washington State may not be as talented as Cal, but with an overall roller coaster season as the Pac-10 has been this year, this week's contest may not be as easy a bounce-back game as one would expect.
"Their O-line doesn't really show run or pass and that gives the D-line and linebackers problems because we're used to having linemen get into two-point for pass and things like that," Jarrett explained, "but other than that, the quarterback has a pretty strong arm. Our secondary needs to step-up and make a few plays. We're a good run-defense so I'm not really worried about the run that much."
Now presented with a less talented opponent, but one that has played some good teams real tough all year, the team as whole, including the defense, must step up and make a statement against an inferior opponent at home on homecoming. The defensive end fully believes that the Sun Devils will play significantly better this weekend.
"We were really embarrassed after that (Cal) game, it really hurt," Jarrett noted, "and if you put us on the field right now we're going to do some damage because that was just embarrassing and we don't ever want that to happen again."