Manny Acta spoke to the media a little while ago about the decision to release Ray King. Basically, Acta said the team's bullpen is too thin right now to carry a lefty who's only there to pitch to left-handers.

"We need an extra-innings type of guy, which right now looks like Saul (Rivera) and (Joel) Hanrahan are the only ones to do it," Acta said. "We need a guy who can pitch to lefties and righties and bridge the gap, like O'Connor."

King was stunned to hear he is headed to Columbus. He didn't know he had options in his contract, and is mulling things over with his agent to see if he should accept the assignment or ask the Nationals for his outright release.

The 34-year-old King impressed Washington during spring training with his conditioning and performance, but it hasn't carried over to the regular season. He has a 5.68 ERA in 6 1/3 innings this season, including what might have been his worst outing of the season last night. He gave up two runs on three hits in 2/3 of an inning against the Mets, allowing a run-scoring bloop single from Angel Pagan when he threw wide of Nick Johnson at first.

"I don't think he will accept (the assignment)," Acta said. "But that's his prerogative."

O'Connor was also a spring surprise after elbow surgery limited his effectiveness in the minors last season. The George Washington product is 2-0 with a 1.96 ERA for Class AAA Columbus this season.

It's hard to say whether the 27-year-old projects as a reliever or starter in the Nationals' future, but Acta said the club at least wants to see him in the majors.

He went 3-8 with a 4.80 ERA in 2006, when he made 20 starts for Washington.

"I haven't had him out of the 'pen yet," Acta said. "We'll see if he can handle it."