"It's still in the works," Johnson said.
Barring an injury, the Nationals don't need Lannan in the postseason rotation. In a short series, they need only four starters.
At Triple-A Syracuse this season, Lannan went 9-11 with a 4.30 ERA. The 27-year-old left-hander also blossomed in his final two starts with the Chiefs, throwing two straight shutouts to end his season in the Minors. He was named the International League Pitcher of the Week last week.