Sean Sullivan ( No. 21 PuRP ) had an up-and-down season.
He made his MLB debut on June 12th in the Las Vegas heat ( while battling illness ) and shined. But that was about the high point for Sullivan, as he bounced between Triple-A and the majors, and also battled an elbow injury.
"It was originally my elbow. It was just, like, some posterior impingement – just some inflammation and stuff like that. Nothing really too serious," he said. "I got it obviously MRI'd and everything, and it came back fairly clean. So I just got a cortisone shot and just rehabbed it and took some rest and was able to come back for those last two weeks of the season."
Sullivan made 14 total starts in Albuquerque, posting a 5-3 record and 5.31 ERA. He was on the injured list from August 3-September 16. In three starts at the end of the year — including one rehab start — Sullivan pitched 6.1 innings across three starts and posted a 2.84 ERA and 1.58 WHIP.
In five big league starts between June 12-July 4, Sullivan went 0-3 with an 8.87 ERA. But he learned a lot during the 2026 season.
"I feel like there were a lot of ups and downs throughout the year," Sullivan said.
"This year for me was definitely a year of growth and learning. Obviously, the debut day was a pretty special day in my life. But … I think just every day I was up there [was a highlight] — just being able to live that experience. And even when I got sent back down, just knowing what I need to get back to and what I'm missing out on."
He continued, "It was a great learning experience, but I take it all for granted, and I'm very blessed to be in the position I am."
His favorite moment? Facing his hometown Boston Red Sox at Coors Field on June 23rd.
"That was pretty cool for me, just being from the Boston area," he recalled. "I grew up loving that team and seeing a lot of those names and facing that lineup was pretty cool for me. So I would say that was probably a special day for me."
But of all the lessons Sullivan learned, he said many of them stemmed from his injury.
"I felt like my body just wasn't in a position where it needed to be physically," he said. "I felt like I was running on fumes almost when I was up there, and I think you could kind of see that with some of my velocity and just my stuff overall wasn't performing as well as it usually does.
"And that ended up showing when I got injured and stuff like that. So I think just getting my body in a better position to where I can go out there for 30 starts and be able to pitch for a full season."
But that also gave him the opportunity to spend some time in Arizona, and now he's back with a plan in place.
He has made two starts so far with the Salt River Rafters, allowing five runs on 10 hits across 5.2 innings with one home run, one hit batter and eight strikeouts.
"I think the idea was to get me innings, but obviously while I'm pitching, I'm always working on something," Sullivan said. "Right now, me and Owen Cuffe have been working on my slider, just kind of changing the shapes a little bit from more of, like, a sweeper to more of a traditional slider, and working and kind of tinkering with different grips and stuff like that with my changeup, as well.
"But I've definitely seen some great progress so far," he continued. "I think taking some of these adjustments into the game has been kind of nice in a less-intense environment rather than in the big leagues where it's hard to make those adjustments."
That was something that senior director of player development, Chris Forbes, said before the AFL season started.
"He missed quite a few starts, so I think we're hoping to get his innings up, and I'm hoping this ends up being a blessing in the sense that once we got him down here, as were kind of letting that calm down, he was able to kind of get to, 'OK, we're going to focus on strength. Let's get the strength back up,'" Forbes said in September.
"He's one of those guys that, during the year, just has trouble maintaining weight. He can come in at 205 (pounds), and now he's pitching at 187 or something at some point. So you're hoping with him that he's able to get some innings back in and get some feel back, and then ultimately make a better decision on how does he play in next year's club. Does he come out of the bullpen as a length guy? Is he doing a spot start? I don't know. But that's the plan with Sean. I'm just looking at five healthy starts and going into the offseason feeling really good about it."
And Cuffe shed some light on Sullivan's new pitch.
"We decided to use this time during the Fall League to work on adding a pitch to his arsenal," Cuffe said via text message. "The goal is give him another pitch to make hitter decision making tougher and have another tool to help him platoon hitters. We wanted to keep the cutter and sweeper in his arsenal and to add a more traditional gyro slider that's more in that 80+ mph range to give him another breaking ball.
"So far, he's had some success with throwing it in our pitching lab, so we will see how it performs to hitters. He's also been working on his movement quality on the mound, which has allowed him to get about 92 mph for the first time in a game this year. Overall, Sean has been working hard and seeing some of the payoffs, so I'm excited for him!"
In the midst of executing his new pitch and overall plan, Sullivan is also enjoying the opportunities afforded to him in the AFL, such as playing with players and coaches from other teams.
"It's really special," he said.
"I think that's one of the coolest parts of this is just being able to kind of pick everyone's brain. And other teams have coordinators in town, and obviously just talking in the dugout and on the bench and stuff, just trying to hear how other teammates do it in their processes and organizations, and I think it's a great way to learn and stuff."
Planning ahead, Sullivan is looking forward to continuing to get better and compete.
"I missed some decent chunks of time this year, and it's never fun," he said. "So I think continuing to get to play – potentially before a lockout, too – is exciting. Whenever I get to take the mound is awesome."
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