Rangers Talent Pipeline: Projecting Texas’ Next Rookie Reliever Promotion

The Texas Rangers have already called up two rookie relievers this season. This one could be the third one day.

The Texas Rangers logo. | Jerome Miron-Imagn Images

The Texas Rangers are closing in on the end of the first month of the minor leagues season and the system has already borne fruit at the Major League level.

Only one of those rookies was a Top 30 prospect, but both have performed well. It shows the amount of time the Rangers are putting into player development already this season.

This week, the focus of Rangers Talent Pipeline is on the next reliever that could make the jump to the Majors.

The Next Rangers Bullpen Call-Up?

Texas Rangers pitcher Robby Ahlstrom. | Arianna Grainey-Imagn Images

So far this season the Rangers have dipped into their Triple-A Round Rock bullpen three times to bolster the staff. Along with Luis Curvelo, who pitched for the Rangers last season, Gavin Collyer and Peyton Gray have made their Major League debuts in the last two weeks and have been tremendous.

So, who’s next? It could be another non-Top 30 prospect who impressed everyone at spring training, left-hander Robby Ahlstrom.

Like Collyer and Gray, the Express have put him in significant high-leverage situations and he’s thrived. Through nine games he is 1-0 with a 2.63 ERA with two saves in three chances along with a hold. He’s struck out 19 and walked three. Only Josh Stephan (23) and Trey Supak (20) have more strikeouts than Ahlstrom.

Gray was the only pitcher at Round Rock with at least 10 innings pitched (12.2) and fewer walks (2) than Ahlstrom, who has only offered three walks in 13.2 innings. He’s the next rookie reliever on stand-by when another injury hits. He’s pitched his way into position.

David Davalillo Proving Worthy of Hype

David Davalillo (@Rangers No. 7 prospect) deals for Double-A @RidersBaseball:

6 IP
3 H
0 R
1 BB
10 K 🔥 pic.twitter.com/sQzs59QVT5

— MLB Pipeline (@MLBPipeline) April 27, 2026

David Davalillo was last year’s Nolan Ryan minor league pitcher of the year last season. He split his time between High-A Hub City and Double-A Frisco. He started this season at Frisco and, if this keeps up, the No. 7 prospect per MLB Pipeline be heading to Triple-A Round Rock.

He won his first game of the season on Sunday, as he went six innings, struck out 10 and only allowed one walk on three hits. It was his most effective outing of the season, but he’s been consistently good so far. In four starts he is 1-2 with a 2.79 ERA and leads the RoughRiders with 28 strikeouts in 19.1 innings. He’s only allowed six walks, but batters are hitting .293 against him. That OBA needs to come down a bit before he can head to Round Rock. But a midseason promotion is not out of the question at this rate.

Anthony Hoopii-Tuionetoa’s Strange Path Continues

Baseball is an odd sport sometimes. Anthony Hoopii-Tuionetoa is proof.

The Pierce (Wash.) Community College pitcher was the Rangers’ 30th round draft pick in 2019. COVID-19’s shut down of minor league baseball postponed his professional debut to 2021. He spent more than three years in the Rangers’ organization before he was dealt to the Chicago White Sox in 2024 so Texas could re-acquire utility man Robbie Grossman.

Well, Hoopii-Tuionetoa boomeranged back to the Rangers on a minor league deal in November and Texas assigned him to High-A Hub City. He may not be long for the Spartanburgers. In six appearances he hasn’t allowed an earned run, saved two games in three chances and has struck out five in nine innings.

With the White Sox he got to Triple-A. Could he do the same for the Rangers? If so, it would be one of the most interesting stories in the minor leagues this season.

Yolfran Castillo’s Sharp Start

Per MLB Pipeline Yolfran Castillo is the organization’s No. 8 prospect. The 19-uyear-old shortstop is off to a productive start at Class-A Hickory.

Through 20 games he’s slashed .284/.370./.420. While he hasn’t hit a home run, he has nine doubles and 15 RBI. He has taken 10 walks and struck out 16 times. He’s also stolen six bases but has been caught twice.

He has an intriguing profile. While he hasn’t shown a lot of home run power, he has gap power, good plate disciple and above average speed. He might play the whole season at Class-A, but his well-balanced work at the plate could get him to High-A sometime late this season.