Ross, who has been out since July 3 with right shoulder inflammation, threw three innings for Triple-A Syracuse on Monday, allowing three hits and one run while striking out two. He threw 42 pitches and will likely require one more rehab outing before returning to the Majors.
Drew, on the disabled list for six weeks with an inner-ear issue that leaves him dizzy, was set to continue his rehab stint with the Class A Advanced Potomac Nationals on Monday, then visit a doctor in Baltimore who has been helping him in recent weeks, manager Dusty Baker said.
Solis, Baker said, is "ahead of schedule" in his rehab from left shoulder inflammation. Baker said the lefty reliever wasn't due to start throwing until next week, but he is about ready to do so now.
"He's champing at the bit," Baker said. "No one wants to get left behind."
The Nationals have held their ground despite a rash of injuries in July and August, but they would love to have all their contributors back in uniform by October.
Ross' absence has meant 10 combined starts, with mixed results, for rookies Reynaldo Lopez and Lucas Giolito. Drew's injury has left the Nationals thin in the infield, with few days off for Danny Espinosa and Anthony Rendon. And Solis' trip to the DL prompted Washington to trade for lefty Marc Rzepczynski.
Thanks to the expanded September roster, the Nationals can get by for the next few weeks without Ross, Drew and Solis, but all three are likely candidates for a postseason roster spot.
Alex Putterman is a reporter for MLB.com based in Washington.