PHILADELPHIA -- The Nationals placed Juan Soto on the 10-day injured list with back spasms on Saturday, retroactive to May 1, making him the latest key player sidelined due to an injury.

He woke up Saturday morning still feeling discomfort in his back for the fourth straight day, so the Nats decided to make the move, electing to exercise caution and not continue playing a man short while waiting out their 20-year-old slugger’s recovery. Andrew Stevenson was called up from Triple-A Fresno to take his place.

“[Soto] was fighting us, but we don't want to take a chance this becomes something bigger,” manager Dave Martinez said. “We've got to get him right.”

Soto’s back issues first surfaced prior to Wednesday night’s game against the Cardinals, when he reported the discomfort while taking swings in the batting cage, and was a late scratch from the lineup. He felt better when he arrived to the ballpark Thursday, but got scratched for a second straight day when his back stiffened again.

Rather than having Soto continue trying to test the injury, the Nationals decided to sit him down for a few days. He will take the next four or five days off to get treatment before he resumes baseball activity. Washington is hopeful he will be able to return from the injured list when eligible on May 11.

“They say I am going to be back soon,” Soto said. “It’s not for a long time. It’s day by day, so how I feel every day is going to make me come back to the field. I’ve been feeling good and better.”

This is the first time in Soto’s brief, but impressive, Major League career that he will spend time on the injured list. He endured a number of different injuries in the Minors, including hamstring, wrist and ankle issues in 2017 that limited him to just 32 games.

In his sophomore season in the big leagues, Soto is hitting .248/.368/.467 with six home runs and a 117 OPS+.

Soto now joins the growing injured list in D.C., which includes Anthony Rendon, who is sideline with a bruised left elbow. Trea Turner is out with a broken right index finger and Ryan Zimmerman is on the shelf with plantar fascitis in his right foot. Trevor Rosenthal is also in West Palm Beach, Fla., at extended Spring Training to work on his mechanics while he recovers from a viral infection.

Turner feels ahead of schedule

It’s been about four and a half weeks since Turner landed on the injured list, but he expressed optimism on Saturday about the recovery process with his broken right index finger. He said he was getting “fairly close” to being able to resume hitting and throwing soon.

“We’re a little ahead of schedule,” Turner said. “I didn’t think we’d be able to do it this early, both of them. But hopefully here pretty soon. Obviously, it depends how I feel. So if I come in and it doesn’t feel good, then we’re not going to progress. But if it does, then we’ll try to keep pushing it and hopefully that stuff happens soon.”

Turner was coy about what exactly he has been able to do since suffering the injury -- “ehhh, stuff,” he said with a knowing smile -- but he said he has been smart about when to test his finger. He has been running as much as possible to keep his legs fresh, and fielding grounders at shortstop without throwing the ball.

At some point during this road trip, the Nats hope Turner will be ready to pick up a bat and start swinging, but how quickly that all happens will depend on how his finger continues to recover.

“Every day it’s kind of how I feel for the most part,” he said. “I’m starting to progress more, able to move the finger more, strengthen a little bit -- not too much, but I think it’s kind of a day-by-day thing.”

Fedde moved to the bullpen

The Nationals are converting starter Erick Fedde to the bullpen. Fedde was initially scheduled to start Friday for Double-A Harrisburg, but after some debate within the organization, the team decided to hold him back from that outing and work on converting him into a reliever.

The move comes on the heels of Fedde’s relief appearance in Washington on April 28, when he tossed four scoreless innings with three strikeouts and a walk in a 7-6 victory over the Padres.

“We want him to get comfortable just coming out of the bullpen first before we decide where we're going to use him,” Martinez said. “But he has to get comfortable. It's a different routine.”

Worth noting

The Nationals traded Austin Adams to the Mariners in exchange for left-hander Nick Wells and cash considerations. Wells, 23, owned a 7.91 ERA in five starts for Class A Advanced Modesto this season.