PHILADELPHIA -- Scott Kingery wore a mask as he took BP for the first time Saturday at Citizens Bank Park.

It did not last.

“It was very difficult for me to breathe,” he said. “I think that’s partially due to the fact that the shortness of breath is still kind of lingering.”

Kingery tested positive for COVID-19 last month. He first felt symptoms June 11. He developed headaches, body aches, fever, chills, the loss of smell, the loss of taste, fatigue and shortness of breath. He said Saturday that he feels fine, but only after he received two consecutive negative tests could he fly from Phoenix to Philadelphia. He arrived Thursday and took an EKG because COVID-19 can affect the heart. He passed the test, which allowed him to rejoin his teammates Saturday.

• Kingery's battle with COVID-19 a cautionary tale

Kingery hopes to play on Opening Day on July 24, but it is unclear if it will happen. He will hit live pitching Monday, which will be an important test. If he's not ready to play, the Phillies could look to non-roster invitees like Neil Walker, Josh Harrison and Logan Forsythe to play second base.

“We can’t rush him,” said Phillies manager Joe Girardi.

Kingery’s experience serves as a cautionary tale for his Phillies teammates.

“It’s been about a month-long thing," Kingery said, "and that’s going to be half the season if you get it during the season."

He said he had trainers come to his house in Arizona after Major League Baseball cancelled Spring Training in March because he wanted to stay in shape. The trainers worked out Kingery, plus a few other players.

“In that way, I was quarantining, staying in my residence, but there were still risks,” Kingery said. “I wasn’t able to say exactly where everyone that I was with was going after those workouts. I eventually was exposed through my workout group. So it’s like, for me, I had to work out to stay in shape for baseball. And at the same time, I was trying to stay as safe as possible, but I ended up getting exposed through my workout group. But yeah, it’s not just a two-week thing because of all the protocols you’ve got to go through. I think there is some stuff with the testing that the virus can stay in your body for a lot longer than we think. So there’s a bunch of stuff you’ve got to go through before you can get back on the field."

But Kingery, even if he feels much improved now, knows the ramp-up will need to be a gradual process.

“I feel good right now physically. My body feels really good. I’ll probably ease back into things over the next couple days at least," Kingery said. "And then hopefully pretty soon get some live at-bats going and then work my way into the games.”

Kingery said he is not sure if he will try to wear a mask while playing again. Didi Gregorius, Jean Segura and Ronald Torreyes wear them while playing.

“I haven’t really gone full force and really tested out what it’s going to be like and how my lungs are going to feel,” Kingery said. “I ended up taking it off to go field ground balls and hitting, but I’ve been wearing it around the clubhouse and any time I’m just kind of standing there.”

That is a requirement these days. One positive test could cost a player a huge chunk of the season, and also cost the team a chance at the postseason.

“That's a tremendous hit for any team,” said right-hander Jake Arrieta, “especially if it's a guy that we count on to be in our lineup every night or one of our starting pitchers, it's going to be tough. I don't mean to be pessimistic, but I feel like it will happen. It was scary to see Scotty get it. It was scary to see Freddie Freeman get hit really hard the way he did. Now it's like, if it can happen to them, it can happen to any of us, right?

“The little things that seemed like an inconvenience at the time like wearing a mask when you go outside or when you're in the clubhouse or when you're around larger groups in meetings, that's just what we need to do to be respectful and courteous to the people around us. There's a lot on the line. There's an opportunity to do something really special in a very strange year. I think everybody here is willing to do that.”