CLEVELAND -- Fresh off his first Minor League rehab outing, Joe Ross joined the Nationals on Tuesday, feeling strong as he nears a potential return.
Ross threw 43 pitches in three scoreless innings for Class A Hagerstown on Sunday. He used the outing primarily to work on his changeup, command and a small mechanical tweak that could help prevent his right shoulder inflammation from recurring.
"More just trying to focus on giving my arm time to get in the right slot because I tend to be a little late sometimes," Ross said. "Which probably is why my shoulder was bothering me in the first place."
Ross was scheduled to throw a bullpen session Wednesday, and manager Dusty Baker said the righty will need at least one more rehab start to increase his pitch count and stamina before he returns to the Majors.
That means Ross will not be available to take his next turn in the rotation, and Washington has not announced who will fill that void. Lucas Giolito, rated the top prospect in baseball by MLBPipeline.com, started for the Nationals on Sunday, but he struggled and was optioned to the Minors after the game, so he must remain there for at least 10 days, barring injury. That makes right-hander Reynaldo Lopez the most likely candidate to be promoted for his second career start, considering Washington purposefully lined up Ross, Giolito and Lopez to pitch on the same day to have options.
But it means Ross will have to wait at least another week before his return to the Majors.
"Pretty frustrating," he said. "Not anyone's fault. Just frustrating not being able to play. Especially days where it would be your start day.
"It's tough, but I've got to get back healthy, back on track and hopefully finish the season strong."
Jamal Collier covers the Nationals for MLB.com. Follow him on Twitter at @jamalcollier. This story was not subject to the approval of Major League Baseball or its clubs.