DETROIT -- The Padres have a rotation vacancy on Saturday, and they’re planning to call up one of their most exciting young arms to help fill it.

Left-hander Jackson Wolf will be promoted ahead of Saturday’s game against Detroit, manager Bob Melvin said prior to Friday’s series opener. Melvin wouldn’t commit to Wolf as the definitive starting pitcher on Saturday, but he noted that Wolf will be called up with the expectation that he’ll pitch at some point.

“Anything, whatever they ask from me, I’m going to do,” Wolf said. “I’m ready to pitch. Whatever they need, I’ll be ready for it.”

The team’s No. 16 prospect, Wolf has posted a 3.39 ERA at Double-A San Antonio this season with 104 strikeouts and just 20 walks across 85 innings. Wolf worked his way onto the big league club's radar with his breakout season, and the Padres had a vacancy with Michael Wacha on the injured list and Ryan Weathers demoted following a poor start in Philadelphia last weekend.

Wolf throws a low-90s fastball with a four-pitch mix, including a slider, curveball and changeup. Despite his 6-foot-7 frame, he’s not a velocity monster. But his unique arm slot has made him an uncomfortable at-bat for opposing hitters.

“Another Double-A guy that’s having a good year,” Melvin said. “Internally, we’re looking for guys to contribute. … Organizationally, they feel like he’s been pitching well. We want to give him an opportunity here. We’ll see what role that is.”

It remains likeliest that the Padres will use Wolf as a starter, but Melvin said Wolf’s role would be contingent upon who else gets used in Friday’s series opener. It’s possible Wolf will be used to cover bulk innings after an opener. It’s also possible that the Padres employ some form of piggyback.

Whatever the capacity, the Padres could use an impressive debut from Wolf. Their rotation has been one of the best in baseball this season, with a 3.69 ERA that leads the National League. But that strong production has come almost exclusively from their starting five of Blake Snell, Yu Darvish, Joe Musgrove, Seth Lugo and Wacha. Due to various injuries and ailments, the Padres have gotten 17 starts from pitchers outside of that group -- who have a 5.73 ERA as starters.

They’re hoping Wolf can help change that narrative while they wait for Wacha to return. (On that front, Wacha, who is working his way back from shoulder inflammation, played catch for a third time on Friday afternoon and could be approaching an early-August return.)

In the interim, the Padres could use a big-time effort from Wolf, a fourth-round pick out of West Virginia University just two years ago. He learned the news in a team meeting after San Antonio’s game in Frisco on Thursday.

“I’m still trying to wrap my head around it all,” Wolf said.