WASHINGTON (CBSDC/AP) — The Washington Nationals have optioned left-hander John Lannan to Triple-A Syracuse and are shifting lefty Ross Detwiler from the bullpen to the starting rotation.

The surprising moves were announced after Washington’s 8-7 loss to the Boston Red Sox in front of a home crowd in DC on Tuesday, two days before the Nationals begin their season against the Chicago Cubs.

Lannan twice has started on opening day, is due to earn $5 million in 2012, and he appeared to have a spot in the starting rotation locked up after Chien-Ming Wang was injured during spring training. But Nationals manager Davey Johnson said the team wants to see “how good ‘Det’ can be.”

Relievers Ryan Mattheus and Craig Stammen made the team.

Washington also selected the contracts of outfielders Brett Carroll and Xavier Nady and first baseman Chad Tracy.

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