Trevor Rosenthal had waited and waited and waited. The Washington Nationals’ right-handed reliever had yet to record an out this season, but he entered Wednesday night’s game in the bottom of the ninth inning with a chance to throw until he got one. The Nationals were leading 15-0. Rosenthal walked the first batter, Philadelphia Phillies first baseman Rhys Hoskins, on four pitches. His wait would continue.

Less than two minutes later, Rosenthal blew his 48th pitch of the season — a 100-mph fastball — by catcher Andrew Knapp for strike three.

The 28-year-old reliever didn’t betray the significance of the moment, his first out since Aug. 12, 2017. Since that day, he had pitched in a game without recording an out for the first time, injured his ulnar collateral ligament, been given his outright release by the St. Louis Cardinals, the team that drafted him. He had endured Tommy John surgery, missed an entire year of baseball, rehabbed and rehabbed and rehabbed, received a gamble contract from the Nationals guaranteeing him $7 million, and pitched in a game without recording an out four more times. Now, under the lights of Citizens Bank Park on a cool April night 20 months after he had last walked off the mound with an out in the big leagues, Rosenthal had come all the way back. He licked his fingers, rubbed his cap and caught the throw back to the mound.

“I felt the same I’ve been feeling, just trying to handle the emotions of being back and the early struggles,” Rosenthal said softly after the game. “My teammates have been incredibly supportive of me. It’s been like a family, like everybody wants me to do really well. So I try to embrace that and keep working hard, and that’s all I can pretty much do.” He paused.

“It’ll all work out in the end. It’s just about learning from it as you go through it, and then eventually, on the backside, I could help anyone else out if they were going through something similar.”

After the strikeout, though, Rosenthal pitched his way back into a jam and allowed a run before closing out the Nationals’ series-winning, 15-1 victory. If Manager Dave Martinez had any lingering uneasiness from Rosenthal’s rough stretch in the lowest pressure situation possible, he didn’t show it.

“He got three outs,” the manager said when asked what Rosenthal should take from this outing. “That’s the key. He got three outs, so let’s continue to build on that and move on.”

Rosenthal knew he would probably pitch Wednesday because he’d talked to Martinez on Tuesday night. Martinez told him they needed to rest some arms in the bullpen and to be ready. Initially, the Nationals didn’t go to Rosenthal — Tony Sipp got one batter, Wander Suero dispatched five — but in the ninth inning of a 15-run game, it was now or never.

“In my outings [before], the more I threw, the better I started to feel,” Rosenthal said. “It was good today to have a situation where I could do that.”

After dispatching Knapp, it appeared as if Rosenthal might be back on track. Two more fastballs, reaching 98 and 99 mph, put outfielder Odubel Herrera down 0-2 in the count. Herrera battled back, fouling off two more pitches, and then watched as three consecutive balls gave him a pass to first base. Rosenthal worked another full count on the next batter, Cesar Hernandez, but walked him as well.

The reliever wanted to stay on the mound. It felt good to get one out, but he wanted to do his best to protect an extended bullpen and prove he could “help this team win.” The bases were loaded but Rosenthal remained stoic on the mound. He attacked the zone on Maikel Franco and eventually induced the slugging third baseman to ground out meekly to first. Though a run scored, Rosenthal had one out to go.

In an at-bat that equaled Rosenthal’s shortest of the night, the reliever got Phillies right fielder Aaron Altherr, who was playing pitcher, to fly out to right on the fourth pitch. Rosenthal had gotten out of an inning for the first time in two years.

After his first three appearances of the season, Rosenthal’s ERA was infinity. He lowered that to 189.00 with the first out Wednesday, then the next two brought it down to 72.00. In the locker room after the game, Rosenthal looked relieved and answered questions in a low and steady voice. Throughout the struggles, which he had heard about from seemingly everyone, he remembered the support from his teammates and Martinez.

“[They] wanted to do whatever they can to help,” he said. “They supported me and [had] my back no matter what. They trust me that it’s all going to work out in the end.”

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