Wallace played two seasons for the Spartans after transferring from Washington in 2014. He graduated from Oak Grove High School in San Jose in 2012. A three-star recruit out of high school, Wallace originally signed with Washington; he attracted offers from other Pac-12 and MWC schools, including San Jose State. After redshirting a year, Wallace played in nine games in 2013, with one interception, nine tackles, and two passes defended. Prior to the Fight Hunger Bowl, Wallace left the program intending to transfer.
In January 2014, Wallace enrolled at San Jose State and later participated in spring practice. The NCAA requires transfers between four-year schools to sit out a season before becoming eligible to compete. To seek a waiver, Wallace filed appeals with the NCAA. By August 2014, the NCAA granted Wallace immediate eligibility to play for San Jose State.
The Mountain West Conference awarded Wallace with honorable mention all-defense honors after the 2015 season. Wallace ends his San Jose State career with 24 starts in 25 games played, 70 tackles, four interceptions, and 18 passes defended. On Nov. 6, 2015, with San Jose State trailing 14-3 to BYU, Wallace had a 61-yard interception return for a touchdown late in the second quarter that pulled San Jose State within 14-10 by halftime. His two other interceptions also led to Spartan scores, on Sept. 19 against Oregon State and Oct. 24 against New Mexico.
Defensive end Tony Ficklin was the last San Jose State player to be an early entrant to an NFL draft, according to team spokesperson Lawrence Fan. A 2004 first-team All-WAC honoree, Ficklin signed with the San Francisco 49ers as an undrafted free agent in 2005. The 49ers cut Ficklin after the preseason, and Ficklin later played in the CFL, Arena2, and Arena Football League.
Other Mountain West football players who will skip their senior years for the NFL draft are San Diego State cornerback Damontae Kazee and Boise State defensive lineman Kamalei Correa.