HOUSTON -- Complaining of soreness in his right hip, Chien-Ming Wang was pulled from his Minor League rehab assignment after another rough outing Tuesday night.

Wang gave up seven runs (six earned) on seven hits and two walks while striking out four in 4 2/3 innings for Double-A Harrisburg on Tuesday night. He gave up three runs in 6 2/3 innings the outing prior to that and four runs over six innings on July 28.

Wang's current rehab assignment was scheduled to end Saturday, meaning the Nationals would have had to activate him or designate him for assignment. But with Wang still on the disabled list, his rehab clock should be pushed back until he can start another Minor League assignment.

At that point, he'll have 30 more days on rehab, meaning he would still be available to call up when Major League active rosters expand on Sept. 1.

Wang hasn't pitched in the Majors since June 30, and his last start for the Nationals was on June 19, when he gave up five runs on seven hits in 3 1/3 innings. The veteran right-hander has a 7.61 ERA and 2.15 WHIP in 23 2/3 innings in the Majors this season.

Jackson joins overworked bullpen for one night

HOUSTON -- Despite pitching a combined 10 2/3 innings in two four-hour marathons to start this four-game series at Minute Maid Park, the Nationals bullpen is in relatively good shape.

Washington manager Davey Johnson said he hasn't heard any of his seven relievers asking for a day off, but he's granting one Wednesday to his two "closer types," Tyler Clippard and Drew Storen.

With a shortened bullpen, Edwin Jackson skipped his usual throw day Wednesday and will join the relief corps just in case a third straight extra-inning affair breaks out and the Nationals need another arm to back up starter Gio Gonzalez. That way, Jackson will get in his scheduled between-starts work and potentially help out a taxed bullpen if they need it.

"This is what we did in the day when we carried 10 pitchers," Johnson said. "A lot of times you'd go to your starter on his throw day and try to get an inning or two out of him."

Clippard has worked five of the past six games, and Storen has pitched in four of the last five. Johnson wanted to stay away from Storen each of the past two nights, but that didn't work out as planned. He was encouraged to see Storen so eager to throw three straight days, albeit with a caveat.

"It was really good. He was lying," Johnson said, breaking into a smile. "When he came in [after pitching Tuesday], he said, 'My tank is empty.' He only faced two batters. But that's the makeup out there. It's always been, all of them.

"He's used to throwing every day. I haven't actually had anybody on this staff come in. I have in the past."

If a save situation does come up with Clippard and Storen unavailable, Johnson likes his options in Sean Burnett, Michael Gonzalez, Tom Gorzelanny, Craig Stammen and Ryan Mattheus.

"I have five guys out there that I'm comfortable with closing with. They've all done it," Johnson said. "We'll see what happens. Maybe Gio goes nine.

"He's been throwing good. He won't be on any pitch count."

Werth returns to lineup after resting legs

HOUSTON -- Jayson Werth was back in the Nationals' starting lineup Wednesday night against the Astros, batting sixth and playing right field.

Werth left Monday's game early due to soreness in his legs, and manager Davey Johnson held him out of Tuesday's starting lineup. Werth did play in Washington's 12-inning win over Houston, knocking a pinch-hit single to right field in the eighth inning.

"Feeling better," Johnson said of Werth. "Not good enough to play center, but feeling better. Hopefully he can make it nine."

Werth returned from his rehab assignment Thursday after missing 75 games, and the Nationals have won every game he's played in since then. Their only loss was the second game of Friday's doubleheader, when Werth sat. In all, Washington went 43-32 when he was on the disabled list but has gone 24-9 with him on the active roster.

The veteran outfielder has reached base safely in 18 straight games dating back to April 21, posting a .408 on-base percentage during that span. He has posted a .471/.591/.471 batting line in six games, five starts, since his return.