MILWAUKEE — The Phillies checked last month with Zach Eflin, asking him one last time if he was ready to pitch the following day after soreness in his right knee kept him on the injured list for a month.

“‘I’m ready to go, I’m ready to go, 100 percent,’” Phillies president of baseball operations Dave Dombrowski said Eflin told them. “There wasn’t even any question.”

So the Phillies activated Eflin on Aug. 26 and removed Chase Anderson from the roster only to scratch Eflin from his start an hour later when the discomfort returned.

“Even if he would have said, ‘I’m not sure,’ we never would have made the transaction,” Dombrowski said. “But he wasn’t even ‘I’m not sure.’ He was ‘I’m ready to go, 100 percent.’ All of a sudden it started bothering him.”

The tear in Eflin’s right patellar tendon that he nearly pitched through will require surgery on Friday, which the Phillies said will require six to eight months of recovery time. For an hour last month, the Phillies were able to imagine entering the offseason with a solidified starting rotation.

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The 27-year-old Eflin was healthy enough to be activated, Ranger Suárez was a revelation after moving from the bullpen, Aaron Nola and Zack Wheeler are both under contract, and Kyle Gibson, acquired at the trade deadline, has a year left on the deal he signed with the Texas Rangers. The starting rotation did not have to be a top priority for the winter.

But Eflin’s second knee surgery in five years ― and the likelihood that he’s not ready for the start of the season ― has changed that.

“Yeah, it changes our thought process for sure because I really didn’t think we’d have to talk about starting pitching because I thought we would be set,” Dombrowski said. “But we’ll have to talk about that in addition to whatever else we want to address.”

The Phillies, just like they did last winter, will need to address their rotation this winter. Here’s how they might go about it.

Internal options

The Phillies had planned to replace Eflin in the rotation with left-hander Bailey Falter, but he tested positive for COVID-19 about two hours after Eflin was first placed on the injured list on July 20. Falter, a starter in the minors, was out for almost a month, and is now working as a reliever since his arm is not fully stretched out. He seems to be the top internal candidate to slide into the rotation.

Left-hander Cristopher Sanchez and Adonis Medina, both 24, are on the 40-man roster and starting at triple A, but seem like long shots to be rotation candidates for the start of 2022.

The Phillies promoted Hans Crouse earlier this week to triple A, which makes the 22-year-old right-hander a candidate. Crouse had a 3.42 ERA in five starts with double-A Reading and struck out 11 batters per nine innings. He has to be added to the 40-man roster this offseason to be protected in the Rule 5 draft.

Some think Crouse, acquired from Texas at the trade deadline along with Gibson and Ian Kennedy, is suited to be a reliever, but the Phils still see him as a starter.

“He’s pitched very well,” Dombrowski said. “He throws multiple pitches. His delivery is different. He’s more of a max effort delivery, I guess, so that’s why a lot of people say maybe a reliever. But he also commands his pitches, so he throws them very well. He doesn’t walk many people. He has command of the strike zone.”

Free agency

The pitching market this winter could include Max Scherzer, Justin Verlander, Zack Greinke and Noah Syndergaard, but the Phillies aren’t expected to swim in those waters. Plus they have more areas to address this offseason besides their rotation.

They will have money to spend as players such as Andrew McCutchen, Odúbel Herrera, Archie Bradley, Matt Moore, Chase Anderson, Brad Miller, and Vince Velasquez are set to come off the books.

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To replace Eflin, the Phillies likely will target rotation depth like they did last winter when they combined to spend $7 million on Moore and Anderson. But they’ll have to hope they get more production than 22 starts and a 6.70 ERA from their investment. Dylan Bundy, Robbie Ray, and James Paxton, who had Tommy John surgery in April, are three early names that stand out.

“There’s just a need to wait until after the surgery takes place, after the healing process takes place, they figure that they’ll have some pulse on him a couple months down the road,” Dombrowski said of Eflin. “They figure it’s now middle of September, so middle of November, that’s a couple months, they’ll have a better feel. That’s when you really start to get into the wintertime process.”

Trade

Dombrowski acquired a pitcher for 2022 in July when he landed Gibson at the trade deadline, a move that seems even more significant when coupled with the Eflin news. It’s usually hard to trade in the offseason for quality starting pitchers, but this seems like a route Dombrowski will try.

He’s been aggressive with trades at his previous stops and showed that in July when he parted with Spencer Howard, a prospect who was almost deemed untouchable by the previous regime. That trade was Dombrowski’s first major move since joining the Phillies, and he’s expected to mold the roster even more this winter.

Dombrowski’s first full offseason with the Phillies was already going to be interesting, and the need for a starting pitcher only makes it more compelling.