A quiet spring morning was interrupted Monday at San Diego State when a white boom box about the size of a shipping container was placed at the bottom of the steps that lead to the SDSU football practice fields.

Aztecs assistant strength and conditioning coach Chris Gordert turned the volume knob to 11, blasting music as players and coaches appeared for the first day of spring practice. The would-be DJ was joined by intern Marcus Clowes to provide a jolt of energy to the proceedings.

Clowes held out an old green time clock that everyone taps — “clocking in” — as they take the field. The clock is the same one the Aztecs used last year, with a subtle difference. The two Mountain West stickers on top of it have been replaced with Pac-12 stickers.

New year. New conference. New team.

“Really good energy,” SDSU coach Sean Lewis said after a spirited 2 1/2-hour workout. “Boys flying around. Explosive plays. Good turnovers. It was clean for the most part. … Good urgency. Good energy. Good start.”

The to-do list for Lewis and his staff includes rebuilding the offensive line, identifying eight new starters on defense and finding a kicker and punter who can approach the high standard set by specialists the past decade.

“It’s easy to have energy on Day 1,” Lewis said. “Now we get to go again tomorrow. The best thing that we get to do is to do this every single day — and one of the hardest things is to do it every single day.

“Spring ball is such an awesome time, roo, where you get a ton of opportunities to get a bunch of reps, a bunch of new tape for these guys to see themselves, to learn from it.”

San Diego State players go through a drill during the first of 15 spring practices over the next six weeks. (Justin Truong / SDSU Athletics)San Diego State players go through a drill during the first of 15 spring practices over the next six weeks. (Justin Truong / SDSU Athletics)

The new normal in college football is 50% roster turnover each year. SDSU’s 2026 spring roster lists 97 players. That includes 32 transfers and nine freshmen who graduated early from high school; they will be joined in the summer by another 15 players from the Class of 2026.

This is Year 3 of the Sean Lewis era. SDSU went 3-9 two years ago, but turned things around last year with a 9-4 finish that included an appearance in the New Mexico Bowl.

“We really harp on the culture here … to build relationships with everybody,” said SDSU senior running back Lucky Sutton, who rushed for 1,297 yards and 10 touchdowns last season. “Creating that culture was really big for us this offseason, and it’s really starting to show on the field. It’s just the first day, but really great effort and great emotions today.

“The culture and the bonds. It’s a new era of football going on with the transfers. We didn’t really have that bond (the first year under Lewis), so to turn around to the second year, we really created that bond. We’re going to make it even better this year, create that bond and culture for this upcoming team.”

Fifteen workouts over the next six weeks will culminate with the Spring game on May 2. It will be played on campus at the practice fields, with a family fair planned as part of the festivities.

SDSU opens the season against Portland State on Sept. 5 at Snapdragon Stadium. It is the first of four nonconference games before the Aztecs begin play in the reconstituted Pac-12.