CHICAGO (AP)The Chicago White Sox placed center fielder Luis Robert on the 10-day injured list because of blurred vision on Friday.

General manager Rick Hahn said the team is ”cautiously optimistic” the slugger and Gold Glove winner will be ready to return when the White Sox open a three-game series against Oakland on July 29.

Chicago also reinstated catcher Yasmani Grandal prior to the opener of their four-game, three-day series against AL Central rival Cleveland. He was placed on the 10-day IL on June 13 because of lower back spasms.

Robert exited Chicago’s win at division leader Minnesota on July 15 in the second inning because of lightheadedness. He was having trouble seeing from a distance and getting jumps on balls, Hahn said.

Robert then missed the final two games before the All-Star break. He was tested in Minnesota and Chicago and has not been participating in baseball activities.

”It was more of the problem of seeing from a distance and in talking with Luis over the last few days, he really hasn’t been challenged in that regard,” Hahn said. ”So at this time, everything seems to have been more or less the status quo. There’s certainly no deterioration.”

A Gold Glove winner in 2020, Robert has been one of Chicago’s most productive players this season. He’s batting .301 with 12 homers and 54 RBIs in 74 games.

Robert missed time in May because of COVID-19. But Hahn said he would ”hate to speculate” whether these symptoms stem from his bout with the coronavirus.

”All I can tell you is I’m not sitting on any information at this time or keeping from you anything, and I fear speculating about COVID is a third rail in society right now. He’s seeing the right people, he’s getting the right tests done.”

Grandal, in his third season in Chicago, was hitting .185 with two homers and 15 RBIs.

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