Wang was pulled off his previous rehab assignment on Aug. 8 because of hip soreness — a re-injury of the right hip he was rehabbing in the first place.

After allowing six runs in 4 2/3 innings on Aug. 7 of his latest rehab tour, Wang was shelved again. The Nationals placed Wang on the disabled list on July with a strained right hip, which they believed to be hindering his delivery and preventing his trademark sinker from diving down.

In the majors this season, Wang has been ineffective and hampered by injuries, a 7.61 ERA in 23 2/3 innings with 14 walks and 12 strikeouts over four starts and three relief appearances.

Wang spent all of 2010 and most of 2011 with the Nationals rehabbing from major shoulder surgery. Wang finished last year strong, and the Nationals signed him to a one-year, $4 million contract this offseason.

The re-injury of his hip came at a good time for the Nationals, as it allowed them to avoid making a roster decision on Wang. His previous 30-day rehab window was set to close Aug. 11, meaning the Nationals would have had to add him to their 25-man roster or remove him from their 40-man roster on that day.

If Wang heals and regains his form, he could be used to bolster pitching depth when rosters expand in September. And when Stephen Strasburg is shut down, possibly next month, he could be handy insurance for starter John Lannan in the rotation.

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