Jim Mora remembers the nerves he had as a first-year defensive coordinator.

In the middle of the 1999 season, he sat in the 49ers office on a Thursday night, the last major day of preparation before gameday. Sitting in the dark alone, he worried about how ill-prepared his San Francisco squad looked. What have I gotten myself into?

Three days later, the 49ers crushed the Atlanta Falcons 26-7, unleashing five sacks and allowing just 144 offensive yards.

Little has changed since those days, even if Mora has already weathered two decades of NFL coaching stress. Now in his second year at the college level, he looks toward UCLA’s season opener on Aug. 31 with similar anxiety.

“I want it to be here quickly and I wish it was another year away at the same time,” he said. “It’s never been anything other than that for me.”

If the 51-year-old coaching veteran still gets nervous, then what of UCLA’s touted freshmen? The Bruins reeled one of the program’s best classes in recent memory, one ranked No. 3 in the country by Scout.com. They will rely on many of those youngsters to fill holes, particularly in the secondary.

“My sense about these kids — and hopefully it’s confirmed as we go through the season — is that it’s not too big for them,” Mora said.

On Friday, he named 17 players who will contribute immediately when they play Nevada at the Rose Bowl. On defense, the list includes five-star defensive end Eddie Vanderdoes — who said he is over his back injury — and nose tackle Kenneth Clark, who has performed well enough in practices to avoid a potential redshirt year.

On offense, perhaps the most prominent names will be Caleb Benenoch and Thomas Duarte. The former, who played before crowds of 25,000 in Katy, Texas, will likely start at right guard. The latter will split reps at Y-receiver/tight end with senior Darius Bell.