SEATTLE -- Veteran catcher Henry Blanco has elected for free agency after declining to be outrighted to the Minor Leagues by the Mariners, the club announced Thursday.

Blanco, 42, was designated for assignment on Tuesday to make room on the 40-man roster for Travis Witherspoon, an outfielder claimed off waivers from the Angels.

Blanco was signed as a free agent by the Mariners in mid-June to help mentor rookie catcher Mike Zunino, and he hit .125 (12-for-96) with three home runs and 14 RBIs in 35 games. He also played 15 games with the Blue Jays to begin the season, hitting a combined .142 with the two clubs.

The Venezuelan native is a veteran of 16 Major League seasons with the Dodgers, Rockies, Brewers, Braves, Twins, Cubs, Padres, Mets, D-backs, Blue Jays and Mariners. He is a career .223 hitter in 971 games and his caught-stealing rate of 42.8 percent is the second highest among active Major League catchers.

With Witherspoon's addition and Blanco's departure, the Mariners' Major League roster remains at 40 players, including three catchers -- Zunino, Humberto Quintero and Jesus Sucre.