The Washington Post's Adam Kilgore is reporting that the Nationals plan to option pitcher John Lannan to AAA Syracuse, ostensibly giving Ross Detwiler the fifth spot in the rotation.

The move would be a stunning decline for Lannan and the Nationals organization. Last year the left hander was the Opening Day starter for Washington (he's earned that honor twice), and won 10 games with a 3.70 ERA. According to the Post, Lannan is assumed to be the highest paid player (due $5 million this season) assigned to the minors this year.

The presumed move of Detwiler to the rotation (even temporarily) means the Nationals will have spots for both Craig Stammen and Ryan Mattheus in the bullpen, aided by the fact that Chad Durbin was signed by the Atlanta Braves on Tuesday, opting out of his minor league deal with Washington.

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