(Alex Brandon/AP)

“Chien-Ming is very valuable to us,” Johnson said. “In the [four] starts, he hasn’t gotten better with his mechanics. I need him. I need him to get right. I really like where his arm strength is at. But I really need him to get back comfortable.”

Wang will work closely with pitching coach Steve McCatty while pitching as a reliever. Wang has been rushing through his delivery, which causes his arm to drag behind his body and prevents him from getting his hand on top of the ball. The result is a fastball that lacks its trademark sink and instead moves wildly across the plate.

The glitch has made Wang ineffective. Wang has a 6.62 ERA over four starts, allowing 14 walks and 26 hits in only 17 2/3 innings. Last night, the Rays drilled seven hits and drew three walks against him as they scored five runs in only 3 1/3 innings.

Detwiler relieved Wang and again showed how dominant he can be at his best. The 26-year-old left-handed retired 11 of 12 hitters in 3 1/3 hitless innings. Since the Nationals moved Detwiler from the rotation to the bullpen, he has responded by allowing two runs in 13 1/3 innings with 10 strikeouts.

“If you compared his performance last night with his last two [starts], he’s a totally different pitcher,” Johnson said. “He was dominating last night. Very aggressive after the hitters.”

With Wang in the bullpen, Johnson will be able to give the Nationals’ other six relievers more work. With Henry Rodriguez and Drew Storen nearing returns from injury, Johnson feels comfortable with the state of his bullpen even with Wang, who because of the shoulder surgery he recovered from last year requires extra time to warm up.

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