NEW YORK (CBS Chicago/CBSNewYork/AP) — Former Cub Anthony Rizzo has tested positive for COVID-19.

The new Yankees first baseman will be out for at least 10 days.

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Rizzo is the fourth Yankees player within the past week to be sidelined by COVID-19, joining starting pitchers Gerrit Cole and Jordan Montgomery and catcher Gary Sánchez.

Rizzo tested positive after Saturday’s game, manager Aaron Boone said. Rizzo went 0 for 4 in the Yankees’ 5-4 victory over Seattle.

Rizzo is off to a quick start since the Cubs traded him away to the Yankees on July 29. The first baseman is hitting .281 with three homers and six RBIs in nine games for the Bronx Bombers.

“I just spoke with him, he’s doing all right,” Boone said before Sunday’s series finale against Seattle. “He’s got symptoms but he’s doing OK. Obviously a little bummed out but hopefully a chance to get rested up and well and be back hopefully sooner rather than later.”

Cole tested positive on Monday, Montgomery tested positive Tuesday and Sánchez was placed on the COVID-19 list on Thursday. Boone said Cole, Montgomery and Sánchez are feeling better.

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The outbreak occurred after the Yankees returned from playing six games against the Tampa Bay Rays and Miami Marlins in Florida, where COVID-19 cases are surging. Rizzo made his debut with the Yankees on July 30 at Miami.

“I think a lot came out of Florida where we were in this wave of them,” Boone said. “It’s a little of you don’t know when and where it’s spreading.”

At least 85% of New York’s players are vaccinated, resulting in a loosening of restrictions, but the Yankees still have been hit hard and Boone said the team will hold conversations about being cautious on its upcoming six-game road trip.

Rizzo, a cancer survivor, said in June he was not vaccinated and Boone did not want to speculate on any player’s vaccination status.

“A large percentage of us obviously are, but I’m not going to get into that anymore,” Boone said.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)

CBS 2 Chicago Staff