He was promoted to director of operations in 2007 and was part of a staff that reached the program's first College World Series.

[2] Wallis moved with Serrano to Cal State Fullerton in 2008, serving as an assistant coach.

The Titans qualified for the NCAA Tournament in all three seasons Wallis was on staff, highlighted by a College World Series trip in 2009.

[3] In 2014, Andy Stankiewicz hired Wallis as an assistant coach at Grand Canyon for the program's first season back at the Division I level.

[1] Several coveted GCU players who had entered the transfer portal — including shortstop Jacob Wilson who was playing with USA Baseball's Collegiate National Team and 2022 Western Athletic Conference Pitcher of the Year Daniel Avitia — announced their return to GCU within days of Wallis' hiring.