Bit of a backtrack for Nationals manager Davey Johnson on Thursday during his pregame media session. He may not start left-handed pitcher John Lannan during the critical series with the Atlanta Braves next weekend. Lannan, of course, is taking the spot vacated by Stephen Strasburg when he is shut down after his Sept. 12 start against the Mets.

But with left-handed relief pitcher Sean Burnett ailing with nerve irritation in his left elbow, Johnson may want to keep Lannan in the bullpen a few days longer. Lannan last started a game Aug. 30 in Triple-A. Johnson expected to skip him one start – what would have been Sept. 4 – and then have him available in the bullpen on Sept. 9, the following day to pitch. That would give Lannan some rest after back-to-back complete games to finish his year at Syracuse and then some time to warm-up again before jumping back into the rotation.

But with days off on Sept. 13 and Sept. 17, Johnson has to consider how his other starters would be affected by Lannan sliding into a spot during the Sept. 14-16 Braves series. Too much rest hasn’t been good for Jordan Zimmermann this season and there’s a chance the others could be thrown off rhythm, too. We’re also close enough to the postseason that Johnson could use the flexibility of his final two days off to set his rotation the way he wants heading into the last week of the regular season.

Presumably, you would want Zimmermann or Gio Gonzalez pitching on regular rest at the very least for a possible wild-card game on Oct. 5. Given Washington’s big lead in the NL East, though, you’d really want one of those two set for Oct. 6 – if the Nats win the division, but are the No. 2 seed – or Oct. 7 if they finish with the National League’s best record and are the top seed. All part of the calculations as Johnson figures out when to pitch Lannan.

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