Heading into his team’s fifth spring practice, USC head coach Steve Sarkisian was worried about his players’ energy. Tuesday’s practice was the first post-spring break session, and Saturday’s practice will be the team’s first at the Los Angeles Memorial Coliseum, so Thursday’s practice had all the makings of a sluggish day.Elder statesman · Junior defensive end Leonard Williams figures to be the key cog in the Trojans’ young defensive line. Williams recorded 74 tackles (13.5 of them for loss) last year on his way to All-American season. – Ralf Cheung | Daily TrojanIn keeping with Sarkisian’s up-tempo philosophy, though, the team showed no signs of slowing down.“It’s easy to be fired up on Tuesday coming off of spring break, and we know on Saturday, going to the Coliseum, they’re gonna be fired up for that,” Sarkisian said. “We wanted to make sure that today we came out with a lot of energy and intensity … and I thought the guys really responded to that.”With an entirely new defensive coaching staff, the unit remains in flux. But Sarkisian is trying to focus on the similarities between last year’s defensive scheme and this year’s to ease the transition.“There’s only so many defenses you can run,” Sarkisian said. “There are probably some similarities in our base front — they were a 5-2 a year ago, we’re a 3-4 hybrid. We’ll probably rely on being in that 3-4 a little more than they did.”Good vibrationsGiven the abrupt nature of former head coach Ed Orgeron’s departure and the loyalty that he was able to establish among current players, some concern lingered about how quickly Sarkisian would be able to “win over” the players.That appears to have been accomplished, as players have been very receptive to the new coaching staff’s instruction. The vibe around the team is as positive as it’s been in quite some time.“Everything is positive, even when you make a mistake,” redshirt freshman cornerback Chris Hawkins said. “We’re having fun — even in meetings. We’re listening to music in meetings while [coach] is talking, so we’re all grooving and taking notes. They keep us uplifted.”With the players’ spirits consistently high, Sarkisian has been pleased with their receptiveness to the staff’s criticism and instruction.“What I’ve been impressed by with this group is when I give them things to work on in the upcoming practice, they really try to apply it,” Sarkisian said. “That’s a sign of a team that wants to do well and wants to do the things the coaches are asking of them.”That type of attitude will be especially useful on the defensive side, where several younger players will be thrust into starting roles, especially on the defensive line.“[The new guys] are coming along great,” said redshirt senior linebacker Hayes Pullard. “Everybody’s messing up, we’re all learning the same new defense and they’re fixing it the next day, which shows maturity for a young guy.”New FacesWith the departure of key players such as George Uko and Morgan Breslin, the Trojan defensive line was expected to have new contributors this year. But with junior defensive end Leonard Williams still out while recovering from surgery, even more new players have been forced into larger roles.One of those players, redshirt junior Delvon Simmons, is more experienced than most. A transfer from Texas Tech, Simmons sat out last season due to NCAA rules but looks ready to contribute immediately. Simmons made 40 tackles in two seasons for the Red Raiders, including three sacks and two pass deflections.“We have a lot of big guys,” Williams said. “We have a lot of potential on the D-line. Delvon has been doing a great job so far. We still need a lot more work, but we have enough time.”Williams said he wouldn’t be practicing at full strength until the summer. Other inexperienced players on the defensive line include redshirt sophomore Jeff Miller and redshirt freshman Kenny Bigelow. Both took reps with the starting defense.QUICK HITSSaturday’s practice at the Coliseum will be the team’s first in full pads. Sarkisian said that there would be a roughly 10-minute, 25-play period with live tackling. “They’re chomping at the bit,” Sarkisian said. “The defensive guys — they want to go tackle some guys.”Sarkisian said that he plans to start fall practices at 8:15 a.m., instead of the normal 4 p.m. Saturday’s practice will start at 11 a.m.