Opening day is next week, and there is concern for New York Mets ace Jacob deGrom and Chicago Cubs first baseman Anthony Rizzo because of back issues. It looks as if New York Yankees star Aaron Judge is feeling much better.

The Mets sent deGrom for an MRI on Wednesday after the right-hander pitched just one inning in a summer camp appearance due to back tightness. An MRI on Rizzo on Tuesday showed rib-head inflammation on his left side that is causing back spasms — a condition he has dealt with before in his career.

“Frustrating, just because how physically in shape I felt like I was coming in,” Rizzo said. “Just can't control the flareups. The MRI getting kind of what we knew, just confirming it. Just kind of getting it to calm down and get back out there as fast as I can.”

New York Yankees right fielder Aaron Judge throws from the outfield during baseball practice, Wednesday, July 15, 2020, at Yankee Stadium in New York. Judge was back on the field after suffering from a stiff neck. (AP PhotoKathy Willens)

New York Yankees right fielder Aaron Judge throws from the outfield during baseball practice, Wednesday, July 15, 2020, at Yankee Stadium in New York. Judge was back on the field after suffering from a stiff neck. (AP PhotoKathy Willens)

Judge has been hampered by a stiff neck, but the outfielder was in the lineup for New York's intrasquad game at Yankee Stadium on Wednesday. The Yankees also said Masahiro Tanaka was scheduled for a bullpen session Thursday in his first action since he was struck on the head by a liner on July 4.

The loss of deGrom or Rizzo for an extended period would be a huge blow for either of their teams — especially in a shortened 60-game season.

The 32-year-old deGrom won his second consecutive NL Cy Young Award in 2019, finishing with a 2.43 ERA and NL-best 255 strikeouts in 204 innings. If deGrom is unable to go on opening day against Atlanta on July 24, Marcus Stroman, Rick Porcello or Steven Matz could get the ball.

“I mean, I think he’s had some history. I think he missed one start a couple of years back because of back tightness," Mets manager Luis Rojas said. "I don’t know if this is related. I think after finding out today what comes out of the MRI, we’ll reassess.”

Rizzo, who is expected to bat second in Chicago's lineup, hit .293 with 27 homers and 94 RBIs last year. Kris Bryant and Victor Caratini could fill in at first if Rizzo has to begin the year on the injured list.

“I think the good news is he understands where he's at with this back thing he's got going on and dealing with it in the past," Cubs manager David Ross said. "He doesn't seem worried. I think the main thing is that we're progressing in the right direction.”

While injuries put the opening-day plans for New York and Chicago in question, the coronavirus continued to have a dramatic effect on rosters across the sport.

Twins first baseman Miguel Sanó was cleared to join the team after testing positive for COVID-19 upon his arrival in Minnesota. Royals catcher Salvador Perez is back after his own positive COVID-19 test. Same for outfielder Anthony Santander in Baltimore and slugger Derek Dietrich in Cincinnati.

“It changed my way of thinking," Dietrich said. "It humbled me and motivated me. I have empathy for anyone dealing with this because it sucks. It really does. I didn’t have symptoms but just knowing and thinking, ‘Well, who was I around?’ This isn’t about you. A lot of people are dealing with this. It is real. It is very real.”

Santander suited up for the first time Tuesday and went through a rigorous workout in an effort to make up for lost time. He is hoping to be part of the starting lineup when Baltimore visits Boston for opening day on July 24.

“This was something serious,” Santander said Wednesday on a video conference call. “Thank God I had only mild symptoms.”

Perez was cleared with a second negative test in a 24-hour period late Tuesday, and Kansas City manager Mike Matheny said the news gave the entire club a boost — especially with Brad Keller, Ryan O’Hearn and Cam Gallagher still sidelined by the virus.

“It was the perfect timing for a shot in the arm,” Matheny said. “Our guys have been just doing such a great job choosing to see the opportunity and refusing to fall into the negativity and excuses and whining and complaining, but when you keep getting a lot of the news we’ve been getting internally — losing this guy or this happens — when you get one of those back, let alone someone the player and personality of Salvador Perez, it couldn’t be any better.”

AP Sports Writers Mike Fitzpatrick, Ronald Blum, David Ginsburg, Joe Kay, Dave Campbell and Dave Skretta contributed to this report.

Jay Cohen can be reached at https://twitter.com/jcohenap

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