"I'd say it's probably fatigue and he's just tired," Ventura said. "There's no pain or anything in there. We'll see how it sits in Minnesota and how he feels. Nothing's changed in how we treat him, we're just trying to take care of him."
The White Sox acquired Francisco Liriano from the Minnesota Twins on Saturday. Liriano, who stayed in Minnesota after the trade, will join his new team for the start of a three-game series in Minnesota on Monday and will start Game 2 on Tuesday.
Sale downplayed the significance of missing his next start.
"It's fine," Sale told ESPNChicago.com. "It hurts a little bit. Just taking some time off right now, but everything's fine."
Ventura also said that Sale is not necessarily a lock to start against the Los Angeles Angels after Minnesota, saying that he could need more rest. There has been speculation as to why Sale's pitching velocity has been lower than usual lately, but Ventura insisted that it's nothing serious.
As far as the possibility of not facing the Angels, Sale said: "Obviously it would be more rest and I'd be feeling a little bit better. But I've just got to put my work in and be ready to go then."
Sale said that he is having no problems in his elbow at all.
There is a chance the Sox could shift to a six-man rotation for a brief period.
Sale, who has thrown 124 innings, experienced elbow tightness earlier in the season, but he pitched through it and made the AL All-Star team.
"The extra time benefits everybody," Sox pitching coach Don Cooper said.
ESPNChicago.com contributor Clint Foster contributed to this report.