During his career he played for the Atlanta Falcons and Los Angeles Raiders of the NFL, the Frankfurt Galaxy of the WLAF, and the Hamilton Tiger-Cats of the CFL.
[2] During his rookie season, he played in 11 of the 12 non-strike games and was primarily used on special teams but did record two quarterback sacks.
In April 1989, Mraz signed with the Los Angeles Raiders, for whom he played in 11 games that year, recording 0.5 sacks.
The Frankfurt Galaxy selected Mraz in the second round (14th defensive lineman) of the 1991 WLAF positional draft.
[3] He finished the season with 6.5 sacks[4] and earned first-team All-World League honors.