Rocker was 2-3 with a 6.66 ERA and one save in 30 appearances with the Rangers in 2002.
He went 1-0 with 8 2/3 scoreless innings in six appearances at Triple-A Oklahoma from May 21-June 9 after initially refusing to report. He was 0-1 with 13.50 ERA in three rehab outings with Tulsa from Aug. 8-12.
He was placed on the 15-day disabled list on July 11, retroactive to July 4, with left shoulder and neck pain, and experienced recurring pain following his rehab assignment at Tulsa.
He did not pitch again.
"John struggled, and as we went through it, we decided to go in a different direction," said General Manager John Hart. "We just decided that was one road we didn't want to go down again."
Rocker, 27, gained notoriety after his negative comments about New York and homosexuals were published by Sports Illustrated in the fall of 1999 when he was with the Atlanta Braves.
Rocker spent his first three-plus seasons with the Braves, recording 88 saves in 180 games. But he came under fire and was suspended by Commissioner Bud Selig for remarks on racial, ethnic and sexual minorities in the SI article.
He was acquired from the Cleveland Indians in a trade last offseason.
He failed to live up to expectations in the Rangers' bullpen. He had been counted upon to be the team's closer, but never pitched well enough.
Also, according to the Dallas Morning News, he got into an argument with a transsexual couple at a popular Dallas breakfast establishment. He did issue a written statement after the incident, but it was deemed insufficient by the Gay and Lesbian Alliance Against Defamation.
During that incident, he said he was having brunch with his girlfriend at Breadwinners Café and Bakery when he was badgered and baited by nearby patrons. He contended a group followed him outside of the establishment and made an obscene gesture.
He also was a target of team owner Tom Hicks, who singled out Rocker in May after a poor outing in Detroit, saying that he "stinking up the joint."
He gave up four runs in his first two appearances of the season and finished April with an 8.59 ERA.
Rocker's release came two days after the Rangers fired Jerry Narron as manager.
Texas also announced it will not pick up the 2003 contract option on backup catcher Bill Haselman.
Haselman hit .246 with three home runs and 18 RBI in 69 games while backing up perennial All-Star Ivan Rodriguez, whose future with the Rangers also remains in doubt.