The Nationals already made one trade today when they shipped Jerry Hairston to the Brewers, and they’re at least preparing in case they send another veteran to a contending team.

Class AAA right-hander Yunesky Maya is traveling to Washington this afternoon to be “on call” in case the Nationals trade a member of their pitching staff, most urgently scheduled starter Jason Marquis, according to two sources. Maya would have started for Syracuse today in Toledo. Because Syracuse is playing so far away, the Nationals did not want to risk being caught short-handed for tonight’s game against the Mets.

Marquis is the likeliest Nationals starting pitcher to be traded before Sunday’s deadline. The Nationals Nationals and Tigers came close to working out a deal for Marquis on Thursday before it fell apart, a source said. The Tigers today acquired starter Doug Fister from the Seattle Mariners, so the window to trade Marquis to Detroit may or may not be closed. The Tigers had a scout in Los Angeles last weekened to watch Marquis start against the Dodgers.

General Manager Mike Rizzo does not feel trading Marquis is an imperative, and he will not be inclined to lower his price. Marquis will make roughly $2.3 million for the remainder of the season, which is why one scout believes Marquis would clear waivers and be a candidate to be traded in August.

Whether or not Marquis gets traded, the Nationals are preparing for it.