Joe Ross has not pitched since 2017 due to a 14-month recovery from Tommy John surgery. (Toni L. Sandys/The Washington Post)

The hardest part for Joe Ross — between the aches and soreness, the worry and waiting, the feeling of not being quite right — was all the lingering doubt.

Ross’s life revolves around throwing a baseball, hard, accurate and everything in between. So when he tore the ulnar collateral ligament in his right arm last July, and needed Tommy John surgery to repair it, there was a fixed recovery plan. And frustration. And fear of what the future may hold.

“The uncertainty of how it will end, if you’ll be back, if I’ll be back, was the toughest part I think for me,” Ross said in the Nationals’ clubhouse this week. “But I kind of just went day-by-day and I am back here now, so it paid off in the end.”

Ross will start for the Nationals against the Chicago Cubs on Friday, 14 months after surgery, and joked that it will be his “debut No. 2.” For Ross, and any other Tommy John recipient, his career can now be divided into the time before and after the procedure. He thinks his change-up improved during the rehabilitation process. His slider is still coming around. But how his pitches feel at first, and however many he throws against the first-place Cubs and their loaded lineup, Ross could use this month to find a footing in the Nationals’ plans.

For much of this season, with Ross and Erick Fedde on the disabled list, the back-end of the Nationals’ rotation has been occupied by an odd mix of Jeremy Hellickson, Tommy Milone and, most recently, rookie Jefry Rodriguez. But with Ross and Fedde activated, and Rodriguez moved to the bullpen due to a drastic innings increase from last season to this one, the Nationals can take a good look at their options moving forward. Fedde, who made his return Tuesday and will start again on Sunday, was their top pitching prospect coming into this season. Ross was a proven depth starter who now has to prove himself again.

“We want to make sure that they’re healthy and performing to the standards that we feel that they’re capable of doing,” Nationals General Manager Mike Rizzo said of what he wants to see from Ross and Fedde in the last month of this season. “And again we want them to perform well enough to win baseball games and to show to us and to themselves that this is something that moving forward we can use in the future.”

A look at the Nationals’ 2019 rotation — an apt exercise given the team’s 69-72 record with 21 games to play — almost certainly includes Max Scherzer, Stephen Strasburg and Tanner Roark. Scherzer and Strasburg are fixtures. Roark is under team control for one more season and has inspired confidence with a strong second half. After that, the Nationals will need to assess their options within the organization and possibly on the free agent market to fill out next season’s staff.

Ross factors heavily into that conversation, along with Fedde and possibly Hellickson, who will be a free agent this winter and could return to the Nationals at a low price. Ross, 25, was 5-3 with a 5.01 ERA when before his surgery. He also started a playoff game for the Nationals in 2016, and though it did not go so well, that indicated his standing with the team at that time. Ross mostly mixes three pitches, a fastball in the low 90s, a slider as his secondary pitch and a change-up sparingly, according to FanGraphs. That slider needs to be sharp as he returns to the mound on Friday, and he will need to be sharp this September as the Nationals flip their attention to what lies ahead.

“Obviously, number one is being healthy,” Ross said of his goals for the coming month, and whether he sees it as an opportunity to solidify a future spot in the rotation. “So as long as I can finish the rest of this year, and feel good and strong, then that’s fine with me. But inside I want to compete, so when I go out to pitch I’m going to go and try to win a game. It’s not really trying to show my worth to the team in these last 30 days. I’m just trying to go out there and win games.”

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