CLEARWATER, Fla. -- Ronny Paulino couldn't give the Phillies what they wanted, so they traded him to the Giants late Friday night for left-handed reliever Jack Taschner.

The trade means Chris Coste opens the season as the Phillies' backup catcher.

It also means the Phillies have a second left-hander in the bullpen while J.C. Romero serves his 50-game suspension.

"We're pleased to add some left-handed pitching depth to our bullpen," Phillies general manager Ruben Amaro Jr. said. "And we just felt, as we evaluated our club, that Coste was a better fit for us."

The Phillies acquired Paulino in a Dec. 10 trade with the Pirates for Minor League catcher Jason Jaramillo, but it obviously didn't work out. Paulino had fallen out of favor in Pittsburgh because of weight issues and questions about his work ethic. Philadelphia manager Charlie Manuel said Thursday he had no problems with the way Paulino worked this spring, but he saw holes in his swing.

Paulino hit just .194 (6-for-31) with two doubles, one home run, two RBIs and 12 strikeouts in 13 Grapefruit League games.

Hours later, the Giants dealt Paulino back to the National League East, sending him to the Marlins for Minor League right-hander Hector Correa.

Taschner, who will make $835,000 this season, also has had a rough spring. He had a 6.23 ERA in 8 2/3 innings in the Cactus League, allowing 10 hits, nine runs -- six earned -- and 12 walks.

Taschner went 3-2 with a 4.88 ERA in 67 appearances last season. He is 8-4 with a 5.01 ERA in his four-year career.

"He has a history of having some success," Amaro said. "We've had some interest in him for some time. While he's struggled a little bit this spring, that doesn't necessarily mean that is how he is going to perform during the course of the season. You also have to evaluate him based on what he's done in the past."

Interestingly, left-handed hitters actually have fared better than right-handers against Taschner in his career. Left-handers have hit .288 against him, although their on-base-plus-slugging percentage was .758. Right-handers have hit .247 against him, although their OPS is a slightly higher .766.

But this trade could mean more than just Coste becoming Carlos Ruiz's backup and another left-hander in the bullpen.

It could pave the way for left-hander J.A. Happ to win the fifth starter's job, although Amaro said nothing has been decided. There had been some thought that if right-hander Chan Ho Park won the fifth spot that Happ could become the bullpen's second lefty, but the arrival of Taschner seems to make Happ's move to the bullpen less likely.

"Is there a rule against having three left-handers in the bullpen?" Amaro said.

There is not, but Park was a successful relief pitcher last season for the Dodgers, which was why the Phils pursued him in the offseason. Happ has less experience in the 'pen.

"Nothing has been decided," Amaro said. "We've just added some bullpen depth. We'll see how Jack fits with our ballclub."