Maybe reuniting with Mazzone can help him turn around his dismal season.

BALTIMORE -- The Baltimore Orioles signed right-hander Russ Ortiz on Sunday, hoping that a reunion with pitching coach Leo Mazzone rekindles the success that made Ortiz a 20-game winner with Atlanta.

"I think Leo is always up for a challenge," Baltimore manager Sam Perlozzo said. "He's usually up for getting someone back on track. It seems like his track record is he's able to do that."

Ortiz was designated for assignment by Arizona on June 13 following 1½ frustrating seasons. After earning a four-year, $33 million free agent deal following a 21-7 season with Atlanta in 2003, Ortiz was 5-16 with a 7.00 ERA in 28 starts with Arizona.

The Diamondbacks cut Ortiz loose despite owing him almost $22 million. Ortiz was 0-5 in six starts this season.

"I've been itching to get back," Ortiz said before throwing a bullpen session with Mazzone before Sunday's game against the Washington Nationals. "I feel great. ... I don't think I have anything to prove. I just want an opportunity."

He represents a low-cost gamble by the Orioles, who are responsible for only a prorated portion of the major league minimum salary of $327,000. Ortiz is scheduled to make his Baltimore debut July 1 in Atlanta in the rotation spot previously occupied by left-hander Adam Loewen, who was optioned to Triple-A Ottawa.

Ortiz said the presence of Mazzone, who joined the Orioles as Perlozzo's pitching coach in the offseason after 15½ seasons in a similar capacity with Atlanta, factored heavily into his decision to sign with Baltimore.

"We had some success ... because of the confidence that they gave me that they were behind me no matter what," said Ortiz, who is 108-76 in nine seasons with San Francisco, Atlanta and Arizona. "The relationship we had, it was great. He was very honest with me."

To make room for Ortiz on the roster, the Orioles optioned Loewen, who was 0-2 with a 7.12 ERA in seven appearances, including five starts.