Ross Detwiler’s return to the Nats rotation is uncertain. (Jonathan Newton / The Washington Post)

Ross Detwiler, on the disabled list since July 4 with a back strain, is not expected to rejoin the Nationals rotation until early next month at the earliest, Manager Davey Johnson said.

Detwiler resumed throwing last week and played catch yesterday. Johnson said the left-hander reported some soreness today after throwing.

Rookie Taylor Jordan is expected to remain in the rotation in Detwiler’s place. Detwiler’s turn in the rotation comes up Tuesday and again July 28 in a doubleheader against the Mets. Johnson all but dismissed the possibility of Detwiler making either start.

“For me, he would have to throw today or tomorrow or do a side and then pitch in a game,” Johnson said. “And I don’t think we’ll be able to do it by then.”

If Detwiler misses next week, his next turn in the rotation would come up  August 1. Jordan, 24, in his first full season since 2011 Tommy John surgery, will be monitored and his innings limited. General Manager Mike Rizzo has said the Nationals have “general parameters” for regulating Jordan’s innings, but Johnson said “it’s not part of the equation yet.” Jordan has thrown a 112 innings between the majors and minors this season, and last season the Nationals pegged his total to around 80 to 90 innings, which includes innings in games and other work such as extended spring training.