The Blue Jays selected Ruiz's contract and put him in the starting lineup Tuesday night against the New York Yankees. He was batting sixth as the designated hitter.
The 31-year-old Ruiz, a Bronx native, hit .320 with 25 homers and 106 RBIs in 114 games with Las Vegas.
Rios was claimed off waivers by the Chicago White Sox on Monday. The White Sox assumed the two-time All-Star's huge contract while Toronto received no compensation.