After going through his normal routine this week and feeling good in a tuneup bullpen session, Jon Lester was activated by the Washington Nationals on Friday afternoon and will start their series opener against the Miami Marlins. Lester, a 37-year-old left-hander, will make his team and season debut after spending close to a month on the coronavirus-related injured list.

To create room on the 26-man roster, the Nationals optioned rookie Steven Fuentes back to their alternate site in Fredericksburg, Va. To make room on the 40-man, they placed Luis Avilán, a left-handed reliever, on the 60-day IL. With Lester in the rotation, the Nationals will start Patrick Corbin on Saturday and Max Scherzer on Sunday. Joe Ross will have his spot skipped, according to Manager Dave Martinez, and probably will face the Atlanta Braves on Tuesday. The team is off Monday.

“We wanted to make sure that, for Jon’s sake, he was good, he was real good to go,” Martinez said of how this decision was made. “And after discussions with him and going through all the protocols that we went through with him, as far as the medical staff’s concerned, he looks good, he feels good and he’s excited to be back. I know that. I talked to him yesterday again, and he’s really jacked up to go out there and help us win.”

Lester was signed in January — to a one-year, $5 million deal — because the Nationals wanted his consistency in the fourth spot of their rotation. He is a lefty who typically takes the ball each turn. More often than not, he can be counted on for at least five innings. But his short Nationals tenure has already been marked by a pair of medical issues.

In early March, he left the team to have one of his parathyroid glands removed. Later in the month, he either tested positive for the coronavirus or was exposed to an infected teammate. He was one of 11 sidelined players and stayed sidelined the longest. Each setback led to another buildup for his arm. The Nationals have been careful not to fast-track him to Washington. His recent weeks were filled with incremental progress in Fredericksburg, and he threw six innings and 90 pitches in a simulated game Sunday.

Now, though, the team has a pressing need for reliable starting pitching. Stephen Strasburg remains on the 10-day IL with right shoulder inflammation. Through four starts, Corbin has been up, down and all over the place. Lester enters the picture at the right time. Martinez said Lester has sat between 87 to 89 mph with his fastball and his cutter has its usual bite.

“This is his first outing of the year, so we’ll keep an eye on him,” Martinez said when asked whether there were any pitch or innings limits for Lester. “The biggest thing for him is to throw strikes. He’s a strike thrower. So we’ll definitely keep an eye on his fastball location, his curveball, his cutter, and we’ll go from there. But I expect him to go out there and go as long as he can.”

While Lester and Strasburg were both out, the Nationals used a four-man rotation of Scherzer, Corbin, Ross and Erick Fedde. That began April 19, a day after Strasburg went to the IL. On Friday afternoon, Martinez told reporters that Strasburg has thrown on flat ground from 200 feet and the team hopes to get him off the mound this weekend. But it’s likely that, starting Friday, the Nationals will have Lester, Corbin, Scherzer, Ross and Fedde, in that order, until Strasburg returns.

And whenever he does, the rotation will become even more of a puzzle. Mixing in Lester is just the first step toward full strength. But the Nationals will tolerate any confusion to have their pitching staff — their expected backbone — in place.