CHICAGO -- White Sox pitching coach Don Cooper, who has been suffering from the dizzying effects of vertigo for the past two weeks, will miss at least the upcoming series at Seattle.

Cooper was around the team for this past weekend’s series against the Minnesota Twins, but left the ballpark before Monday’s game against the Texas Rangers and hasn’t been back.

“He’s off the flight today,” manager Robin Ventura said. “I would say he’s out of the Seattle series. He’s just not feeling any better. It wouldn’t do him any good to get him on a plane. The doctors have basically said ‘Don’t fly. That would be the worst thing you could do right now.’ Just be here, get some treatment and figure out what’s going on.”

White Sox pitchers have struggled of late, especially out of the bullpen, but Ventura didn’t think that was largely the result of Cooper being away.

“I would say some; you would like to have him back,” Ventura said. “I don’t know if (his presence) is 16 runs worth, but we’d like to have him back and be here working. I’d like to have him here. He would like to be here. Pitchers would like him to be here. But I don’t think it’s 16 runs worth.”

The White Sox lost Sunday’s game 16-3 to the Twins and lost 16-0 on Tuesday night against the Rangers.

It will be determined if Cooper is well enough to fly to San Francisco for the brief two-game series Tuesday and next Wednesday at San Francisco. If he isn't on the bench then, his return doesn't figure to happen until the White Sox are home for a three-game series against the Blue Jays starting Aug. 15.

Bullpen coach Bobby Thigpen has taken over the pitching coach duties in Cooper's absence.