MESA, Ariz. — The last thing the White Sox wanted heading into an Opening Day series with the World Series champion Houston Astros was uncertainty about the status of one of their top players, but that’s what they’ll have until third baseman Yoan Moncada is declared fit to play.

While expressing some optimism that the sore low back area that caused Moncada to leave a Cactus League game after two innings Sunday won’t be an issue, first-year manager Pedro Grifol was in wait-and-see mode.

A year ago, Moncada suffered an oblique strain in the last day of spring training and landed on the injured list the day before the season opener in Detroit. He didn’t play until May.

“He’s doing OK,” Grifol said Monday morning before the Sox’ second to last game of the Cactus League season. “He felt a lot better coming in this morning and everything I’ve gotten back is positive feedback.”

Grifol said the expectation “right now” is that Moncada will be ready for Thursday, but time will tell. After Tuesday’s spring finale against the Cubs Tuesday, the Sox fly to Houston, where they will have an optional workout at Minute Maid Park Wednesday. Moncada will get treatment “and do some stuff” there, Grifol said. The soreness is in the low back and “butt cheek” area, Grifol said.

“If everything checks out, he’ll be ready,” Grifol said.

Grifol suggested Moncada’s soreness could stem from being on long flights in recent weeks. He Luis Robert played for Cuba in the World Baseball Classic, flying to Taiwain from Phoenix, then to Miami and back to Phoenix.

“They got a lot of miles on them this spring,” Grifol said. “That could be a residual of that.”

Hanser Alberto would be an option at third base if Moncada isn’t ready Thursday.

On a more positive note, Andrew Vaughn played his first game since March 12 after missing time with low back soreness of his own. Vaughn played in minor league games Friday and Saturday.

Moncada never found a rhythm after his late start to the season in 2022, finishing with a .212/.273/.353 hitting line. He came to camp early, preparing for the WBC and determined to have a bounce-back season. Starring for Cuba, he made the WBC all-tournament team.

“He’s been really working hard,” Sox hitting coach Jose Castro said. “We worked on a couple of things. More lower half stuff, staying behind the swing more. We like where he’s at.

“He got on a roll [in the WBC] and it was working. I think he’s happy where he’s at right now.”