SAN DIEGO -- Fernando Tatis Jr. is on his way back to the Padres.

When, exactly? The Padres aren't saying. But on Thursday, manager Mike Shildt acknowledged for the first time a "looser timetable" regarding Tatis' return from the stress reaction he sustained in the femur bone in his right leg earlier this season.

Prior to the Padres’ series opener against the Mets, Tatis ran sprints in the outfield -- a notable step in his recovery. He then proceeded to play long toss, and Shildt later revealed that Tatis could hit on the field as soon as this weekend.

"He did some sprint work today, which is great -- around 70 percent," Shildt said. "Which is a clear sign of progression. I did meet with him. We have a looser timetable now, but we won't really share it. ... But he's definitely progressing to get back to play. It's good news."

Tatis hasn't played since late June, when he landed on the injured list. He'd spent most of the first half playing through pain in his right leg. But it wasn't getting better, and the Padres shut him down over concerns the stress reaction could develop into a season-ending stress fracture.

Tatis spent the next month or so doing very little. When he was shut down, it hurt to get out of bed, he said. Significant healing needed to take place.

Tatis underwent an MRI during the All-Star break which revealed that healing to be in effect, albeit slowly. Afterward, Tatis began to resume light baseball activity, playing catch and taking dry swings. He was transferred to the 60-day IL on Wednesday, but that move was only procedural. (Having already spent 60 days on the IL, Tatis can be activated whenever he’s healthy.)

"He's been healing," Shildt said. "There's probably going to be more imaging taking place, just to create more understanding of the baseline. But [team doctors] clearly feel there's been enough healing and rest to take place to allow him to progress."

The Padres have thrived in Tatis' absence. They've posted the sport's best record in the second half and sat tied with Arizona atop the National League Wild Card standings ahead of Thursday's game.

But they could certainly use Tatis' bat in the middle of their lineup. Even while playing through obvious pain for the first half of the season, Tatis posted a .279/.354/.468 slash line and was named to the NL All-Star team. His return would theoretically push David Peralta into a bench role as a pinch-hitter, giving San Diego one of the league's deepest offenses.

Ultimately, the Padres' internal timetable for Tatis is unclear. But throughout his stint on the IL, the team has offered a refrain that it won’t take long for Tatis to get ready once he begins to ramp up.

Well, he’s ramping up. Shildt alluded to the possibility that Tatis would skip a Minor League rehab stint altogether. It's possible, Shildt said, that Tatis would instead face live pitching in the afternoons at Petco Park. Then, when he's ready, he'd get a few at-bats in a game-like setting at the team's Spring Training complex in Peoria, Ariz.

"He loves playing this game," Shildt said. "He's champing at the bit to go compete with his buddies and be a part of what we're doing here.”