Cal Poly transfer QB Ty Dieffenbach commits to UCLA

Former Cal Poly quarterback Ty Dieffenbach has committed to UCLA, via the NCAA Transfer Portal, per On3’s Pete Nakos. Dieffenbach began his collegiate career at Pittsburgh, where he spent two seasons.

Dieffenbach made nine appearances for Cal Poly this past season. He completed 56.8% of his pass attempts for 1,305 yards and nine touchdowns, while throwing nine interceptions. Additionally, Dieffenbach recorded 321 yards and four scores in the ground game.

Dieffenbach never saw any action during his two seasons at Pittsburgh. He redshirted his true freshman season.

Ty Dieffenbach played high school football at Agoura (CA), where he was a three-star prospect. He was the No. 1,485 overall player and No. 76 quarterback in the 2023 recruiting cycle, according to the Rivals Industry Rankings.

At the time of his commitment to UCLA, he was the No. 190 QB in On3’s 2026 Transfer Portal Player Rankings. He is the 22nd player who has committed to the Bruins via the NCAA Transfer Portal this offseason.

As of this report, UCLA boasts the No. 12 class in On3’s 2026 Team Transfer Portal Rankings. The Bruins are undergoing significant roster turnover as they enter Year 1 of the Bob Chesney era.

Chesney was James Madison‘s HC the past two seasons. He led the Dukes to a 12-2 overall record in the 2025 campaign and the program’s first-ever College Football Playoff appearance. The 48-year-old head coach is excited to bring a winning tradition to UCLA.

“UCLA is willing to do what it takes to build a championship-level program,” Chesney said in a statement. “UCLA is a very special place. From its stellar academics, impactful alumni, geographic location and deep recruiting base, this is a program that can and WILL win at the highest level.

“UCLA has every ingredient necessary, but what has truly stood out to me is the passion of UCLA’s administration, alumni and fanbase. Their pride, their energy and their willingness to support and invest in this program’s rise create powerful momentum for what’s ahead. Leadership is ready. The alumni are ready. The fanbase is ready. And I am ready. I look forward to working together as we bring this program to the standard of excellence it deserves.”

To keep up with the latest players on the move, check out On3’s Transfer Portal wire. The On3 Transfer Portal Instagram account and Twitter account are excellent resources to stay up to date with the latest moves.