Left-hander Barry Zito, who pitched in Triple A and briefly with the Athletics this season, has announced his retirement in on article on The Players' Tribune.
Zito sat out last year before getting the itch play again this season.
Zito, 37, went 165-143 with a 4.04 ERA in parts of 15 big league seasons with the A's and Giants.
He won the 2002 AL Cy Young award after going 23-5 with a 2.75 ERA .
Zito also won three World Series rings with the Giants in recent years.
In 2015, Zito spent most of the season in Triple A before being called up to Oakland at the end of season.
He and longtime A's teammate Tim Hudson started against each other on September 26, in what amounted to a huge farewell party.
