TORONTO -- The Rangers' quest for bullpen help has led them to acquire right-handed reliever Koji Uehara from the Orioles for pitcher Tommy Hunter and first baseman Chris Davis. The trade was officially announced Saturday night.

"Koji is one of the most effective relievers in the game this year and the past couple of years," Rangers general manager Jon Daniels said. "He's battle-tested, he's done it in the American League East, he's a strike-thrower and he has swing-and-miss stuff. We felt he was the right fit for the club. Our scouts were on him and strongly recommended him."

The Rangers had interest in Padres closer Heath Bell, but did not want to give up any of their top prospects from the farm system. The Padres had interest in top pitching prospects Martin Perez, Joe Wieland and Robbie Erlin, but the Rangers were clearly reluctant to go there. Instead the Rangers parted with two players who they had a high regard for in the past, but had slid into less meaningful roles as a middle reliever and backup corner infielder.

Bell is also going to be a free agent after this season. Uehara has a vesting option in his contract and needs just 12 more appearances to be signed at $4 million for next season. He can become a free agent after 2012.

"The attractive part of this deal is three-fold," Daniels said. "First and foremost, we really like Koji. The second part is he'll probably be back next year. It's nice to have a bullpen piece that we're excited about already in place. Third, we like Tommy and Chris, but for this moment in time, they are not filling critical roles. Those are roles that other guys can fill and this allows us to not trade guys who are a little more high-end pieces."

Trade Include

Uehara is expected to join the Rangers on Sunday in Toronto. The Rangers will also activate infielder Andres Blanco off the disabled list to replace Davis on the 25-man roster.

"There are two contradicting feelings," Uehara said in Baltimore after learning of the trade. "Part of me says that a contending team wants me, and that's gratifying. At the same time, Baltimore -- I've been there for two years. It's really sad."

Daniels said the Rangers are still talking with other teams, and it may be possible they continue to talk with the Padres about Bell. But he said he had nothing going at the moment as of Saturday night.

"We're open to that but this takes the edge off it," Daniels said. "We haven't stopped all conversations. If something makes sense, we're open to improving the club. Until four o'clock [Sunday] I wouldn't rule it out."

Uehara joins Mark Lowe in giving the Rangers two proven right-handed setup relievers in front of closer Neftali Feliz. Uehara has pitched in 43 games for the Orioles and is 1-1 with a 1.72 ERA while holding opponents to a .152 batting average. Left-handers are hitting .136 off him while right-handers are batting .171.

In 47 innings, he has allowed 25 hits and eight walks while striking out 62. He has not allowed a run in 11 innings in July. He is 36 years old and this is his third season in the United States.

His two primary pitches are a fastball that averages 88.1 mph and a split-finger fastball. He also has a slider that he uses only occasionally. He ranks fifth in the American League among relievers with 11.87 strikeouts per nine innings. His ratios of 7.75 strikeouts per walks as well as 6.32 baserunners per nine innings are the highest among A.L. relievers.

"They have a great lineup and great starting pitching," Uehara said. "They give me a chance to pitch, and I'll do my best."

The risk is that he has had injury problems the past two seasons. He has been on the disabled list four times, twice with a strained left hamstring and twice with a strained right elbow. But he has not allowed a run in nine games this season in which he was pitching for the second straight day.

He also has to adapt himself to the intense Texas heat.

"Maybe that's one big concern that I may have," Uehara said. "I'm not sure, yet, but maybe."

He was an outstanding starting pitcher for Japan for the Yomiuri Giants from 1998-2008, going 112-62 with a 3.01 ERA. He was a two-time winner of the Eiji Sawamura Award, which is the Japanese equivalent of the Cy Young Award. He was a member of the Japanese team that won the World Baseball Classic in 2006 and has never lost a game in international competition, including two Olympics.

The Orioles originally signed him to a two-year, $10 million contract on Jan. 13, 2009. He signed a one-year, $3 million extension last offseason that calls for a $4 million vesting option for next season if he pitches in 55 games. He is 12 games away from that option being automatically exercised. The Rangers will get $2 million in salary relief for 2012 from the Orioles.

Hunter was 1-1 with a 2.93 ERA in eight relief appearances for the Rangers. He was a 13-game winner as a starter for the Rangers last year. He was supposed to be in the Rangers' rotation at the start of the season, but strained his right groin muscle at the end of Spring Training. He missed three months and was never able to regain his spot in the rotation. The Rangers have been using him in middle relief since he came off the disabled list.

"Baltimore was interested in acquiring a controllable young starter, and Tommy has shown he can get the job done," Daniels said. "Except for a couple of minor injuries, he has shown he can get the job done. He's durable, he throws strikes and has a good makeup. Fortunately for us, we have a rotation that's performing at a high level 1-5, and we've got Scott Feldman and we have a lot of guys [in the Minors] coming behind them that we really like."

Davis was the Rangers' Opening Day first baseman in 2009 after hitting .285 with 17 home runs and 55 RBIs over 80 games in the second half of the 2008 season. But he has not been able to return to that level and has been bouncing back and forth from Triple-A over the past three seasons.

At Triple-A, he has a .337 batting average and a .609 slugging percentage over the past four years. In 48 games at Round Rock this season, he was hitting .368 with 24 home runs and 66 RBIs as well as an .824 slugging percentage. The Rangers called him up from Triple-A for a third time on July 23 when Adrian Beltre went on the disabled list, and he is hitting .250 with three home runs and six RBIs in 28 games at the big league level.

"Chris is in a good spot," Daniels said. "He understands where we are as a club and our winning expectations. Other guys have come along and claimed spots, and it was unlikely that he will get a regular job here barring injury. Where he is in his career, he has a better chance of performing at a high level somewhere else. Baltimore was looking for a corner bat. I wish him all the luck in the world."

Daniels said he understood the possibility that Davis could end up being a "late bloomer" like Nelson Cruz and develop into a high-impact offensive player.

"If he does, we'll live with it," Daniels said.