Nationals manager Davey Johnson said Lannan will make one more start for Triple-A Syracuse, the Chiefs' season finale on Sept. 3, before getting called up to the Majors to replace Strasburg in the Nats' starting rotation.
"I think it's going to pretty much coincide fairly close with Stephen, when he's shut down," Johnson said. "I think the timing, he's lined up almost the same day, so he may have to miss a start."
Johnson said he may have Lannan do work on the side or throw a simulated game rather than put him in the bullpen in the time between his callup and Strasburg's shutdown. That would mean Strasburg, who has thrown 145 1/3 innings entering his start Tuesday, is still on track to finish his season in mid-September.
Johnson remains confident that Lannan is up to the task of filling in for his ace.
"I think he's a great pitcher," Johnson said of Lannan, who is 2-0 with a 3.46 ERA in two big league spot starts this season. "He pitched two great ballgames for us up here, and [it's] nice to see he's throwing well. He's used the time to work on some things. I'm sure he's in a good frame of mind, and it couldn't come at a better time."