Jeremy Hellickson will miss at least one start. (Jeff Roberson/Associated Press)

The Washington Nationals will place Jeremy Hellickson on the disabled after an MRI exam revealed the right-hander’s right wrist is sprained, Manager Dave Martinez announced Friday. The move, however, has yet to be made official, seemingly because the club is waiting to learn whether Stephen Strasburg can replace him in the rotation.

Strasburg has been on the disabled list since July 25 with a pinched nerve in his neck. He threw four “innings” in a simulated game Wednesday and will throw a bullpen session Saturday. If he emerges unscathed, Strasburg could return as soon as Tuesday, when the Nationals open a crucial three-game series against the Philadelphia Phillies. Washington also could decide to call up a reliever to bolster a bullpen that needs help for at least a couple of days until Strasburg is activated.

Hellickson injured the wrist when he landed awkwardly while covering home plate in Wednesday’s loss at the St. Louis Cardinals, and he hasn’t been able to flex it since. The MRI exam results ruled out throwing a bullpen session. Martinez indicated he thinks Hellickson’s DL stint will be short, but that remains unknown. The 31-year-old has a 3.57 ERA in 18 starts.

“He’s still pretty sore and said he hasn’t gotten any better,” Martinez said. “So we’ll have to wait and see. But hopefully with treatment it’ll get better quick.”

As for the bullpen, Martinez said Sean Doolittle was scheduled to throw a bullpen session Friday. Doolittle hasn’t pitched since July 6 because of a pinched nerve in his left foot. Doolittle’s absence was a blow, but the Nationals figured they could adequately absorb it with their bullpen depth. But that depth has vanished since Brandon Kintzler was traded, and Kelvin Herrera and Ryan Madson landed on the disabled list.

Instead, Koda Glover, who missed the first four months of the season, is handling the ninth inning. The hard-throwing right-hander surrendered a walk-off home run Monday but tallied his first save Thursday.

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