Craig is sidelined by a left mid-foot sprain and he's wearing a boot to immobilize the injury sustained rounding first base Wednesday in Cincinnati.
"I think in the short term he's not going to be available anytime soon," Mozeliak said Friday. "I don't want to guess when he may or may not be ready, but I think it's not imminent."
Craig has had a pair of MRI exams that showed no fracture and met with a handful of doctors whose opinions have the Cardinals cautiously optimistic.
"Originally I was pretty scared because my foot's never bent that way," Craig said. "To get that news is huge, and giving me a chance to at least potentially come back this season is good."
Craig was among the NL leaders with 97 RBIs and was batting .454 with runners in scoring position, the best in the majors. He said the foot felt "pretty good."
The Cardinals returned from a 2-5 trip and were 1½ games behind the Pirates with 22 games remaining entering Friday. Mozeliak said if he'd been asked in March, he'd have "absolutely" taken that scenario.
"There's always sort of the ups and downs and the ebb and flow of the season," the GM said. "We're back home, we've got a lot of home games on our schedule, so I feel pretty good about where we are."
The Cardinals activated pitcher Jake Westbrook from the 15-day disabled list, but he'll be in the bullpen for now instead despite the rotation's recent struggles.
Mozeliak thought Lynn had been "picking a little bit" and ending up with deeper counts. Lynn gave up three homers in a loss against the Reds on Wednesday and has allowed 11 runs and 17 hits in nine innings in his past two starts.
"You start losing your advantage when you go from 0-2 to 3-2," Mozeliak said. "Typically when pitchers are having success, they're able to get quick outs."
It's not much leeway for Lynn, who is 0-5 in his past six starts.
"The definition of insanity is repeating the same thing over and over again and hoping for a different outcome," Mozeliak said. "So at some point something has to give."
The 35-year-old Westbrook went on the DL on Aug. 22 because of a lower back strain, and rejoined the roster Friday for a three-game series against NL Central-leading Pittsburgh.
He's 7-8 with a 4.49 ERA in 19 games, all but one of them starts, and earned his 100th career victory earlier in the season.
"We'll try to get him some work," Mozeliak said. "There's no place for him to rehab, so here we go."