The Washington Nationals placed left-hander Andrew Chafin on the 15-day injured list Saturday with a right hamstring strain.

The move is retroactive to Wednesday.

Chafin, 34, has a 3.18 ERA without a decision in 16 relief appearances with Washington this season.

Also on Saturday, the Nationals recalled right-hander Ryan Loutos from Triple-A Rochester. He was claimed off waivers from the Los Angeles Dodgers and optioned to the Red Wings.

Loutos, 26, has posted a 2.75 ERA with three saves while recording 16 strikeouts in 19⅔ innings with three Triple-A teams. He allowed five runs on four hits in three innings over two relief appearances with the Dodgers this season.