BOSTON -- Salvador Perez walked off the field and into the Royals dugout donning catcher’s gear -- and a smile.

The 29-year-old, who is sidelined for the season after undergoing Tommy John surgery on his right elbow in March, made progress in his rehab on Monday. He completed two sets of 25 throws from 45 feet prior to the Royals’ series opener against the Red Sox at Fenway Park.

“It’s one of the best moments of this year for me,” Perez said.

After suffering a partial tear of the ulnar collateral ligament, Perez said he felt “normal” as he focused on footwork, throwing and catching Monday. He plans to do the same throwing routine three times a week for the next two weeks.

“It’s hard work,” Royals manager Ned Yost said. “It’s before we get to the ballpark, it’s while we’re at the ballpark. … [People] don’t understand how exhaustive the rehab process is. … The work you have to do to rebuild that area and maintain your athleticism and body strength. Five hours a day, probably. It’s a lot.”

To help with the recovery process, Perez reached out to players who have been in his situation, including Red Sox starting catcher and friend Christian Vazquez, who underwent Tommy John surgery in 2015. Perez has been happy to stay involved with the Royals in a veteran leadership role, but it was a special feeling getting back into action during this phase of his rehab.

“I feel like I was going to catch tonight,” Perez said with a laugh. “After five, six months [of being inactive], doing that today, for me, was a lot. It was a big step for me.”

The six-time All-Star is looking forward to returning to the field for good.

“I can’t wait to get back to Spring Training and play,” he said. “That’s one of my goals. I’ve got to go step by step and see what happens.”

Mondesi making strides

Adalberto Mondesi also joined the Royals in Boston. The shortstop is recovering from left shoulder subluxation and has been on the injured list since July 17 after diving for a foul ball.

“It feels a lot better,” Mondesi said. “I can do a lot of stuff on the field. I just need to be careful and keep working, but right now I’m feeling pretty good.”

Mondesi has been taking grounders and swinging off a tee. He said he could return in two weeks, but that depends on his progress.

“Right now I can move [my left shoulder] and I can do baseball stuff, because when it happened, I could not move it and it hurt,” he said. “But right now I feel more normal.”

Like Perez, Mondesi made the trip to Fenway Park as the Royals begin to incorporate the injured players into more activity on the field.

“[I miss] everything. Playing with my teammates, being able to do what I love,” Mondesi said. “It’s tough, but it happens. I just need to stay with my head up and stay focused and keep working to be back soon.”