This Royals prospect has strong pitching metrics. How soon will he arrive in KC?
AI-generated summary reviewed by our newsroom.
- Colleran routinely throws upper‑90s and can touch triple‑digits with leg kick.
- He had a 2.85 ERA, 72 K, 34 BB and .161 opponents' average in 66⅓ innings.
- Extended MLB camp and four scoreless spring innings aid his roster evaluation.
The Kansas City Royals are likely set within their bullpen this season. The club has established veterans such as Carlos Estévez, Matt Strahm and Lucas Erceg leading the way.
The relief group is a core strength of the team. The veteran experience will bolster the club in the late innings — and it could lead to decisive victories.
“I think we certainly raised our floor, and there’s going to be some good competition,” Royals pitching coach Brian Sweeney said. “There may be guys that deserve to be in that bullpen. You know, there might be six guys competing for one spot.”
One of those guys is hard to miss. Royals prospect Dennis Colleran has generated attention due his electric fastball and big leg kick.
Colleran was selected in the seventh round of the 2024 MLB Draft. He climbed three minor-league levels in 2025 — reaching Double-A Northwest Arkansas in late September.
In 44 appearances, Colleran posted a 2.85 ERA with 72 strikeouts and 34 walks. He held opponents to a .161 batting average in 66 ⅓ innings.
There were encouraging signs along the way. Colleran dominated High-A batters with a 25% strikeout rate and continued to thrive in the Arizona Fall League.
“I love strikeouts,” Colleran said. “Love seeing guys miss the ball with the bat.”
Colleran can touch triple-digits with his fastball. He routinely throws upper-90s and is balancing his pitching arsenal with a cutter and sweeper.
However, it’s the big leg kick that confuses hitters. Colleran extends his leg horizontally and brings it near his shoulders. The movement helps him be deceptive throwing down the mound while also generating velocity.
He used the unique delivery as a kid. Now, it’s part of his pitching aesthetic and helps him dominate in the strike zone.
“It just kind of helps me get my body moving forward,” Colleran said. “I feel like I want to get down the mound fast. I want to get my body moving fast. I also feel like it’s a little intimidating for guys seeing a leg kick that high. It’s something that I’ve always had and it hasn’t hurt me. So I’m going to keep it that way.”
Colleran hopes to manage his command this season. He posted elevated walk numbers and would like to cut that down in 2026. This spring, he is getting an extended look in big-league camp.
He is off to a great start.
Colleran has pitched four scoreless innings in four appearances. He has allowed one hit while striking out three batters. Additionally, he hasn’t issued a walk while recording a hold and a save.
“I always try to bring the same intensity to every game no matter what,” Colleran said. “I know it’s spring training, and, you know, obviously I’m not trying to go full blast and get hurt, but I always want to have that same intensity out there.”
The Royals continue to evaluate their overall roster. It’s possible Colleran could be a guy that winds up in Kansas City at some point in the future. He has the ability to develop into a late-innings relief option moving forward.
In recent years, the Royals have done well with emerging prospects. Guys such as Steven Cruz and Luinder Avila have matriculated through the minors. They arrived to the team and pitched in key spots.
Colleran is a name to watch this season. If he returns to Double-A and pitches well, there could be a real conversation about his next steps in the organization.
For now, Colleran has a fastball that is noticeable. And a career that could potentially reach a new level with the Royals.
“I’m happy to be here and, you know, for the opportunity to work with some of these guys,” Colleran said.
