Intriguing Nationals Prospect Has One of ‘Nastiest Changeups in Sport’

The Washington Nationals will get a chance to see their new Top 30 prospect pitcher during Arizona Fall League action next month.

Washington Nationals hats and gloves in the dugout against the Pittsburgh Pirates during the sixth inning at PNC Park. | Charles LeClaire-Imagn Images

When the Washington Nationals dealt outfielder Alex Call at the trade deadline in July, the return was two minor league pitchers, one of which is heading to the Arizona Fall League.

Right-hander Sean Paul Liñan posted impressive numbers with both the Dodgers and the Nationals in the minor leagues, with his season ending in mid-August with a trip to the High-A Wilmington Blue Rocks’ injury list. He’s healthy enough to get some additional innings in the AFL, which starts next month. He is also the Nationals’ No. 14 prospect per MLB Pipeline.

He had a season intriguing enough for Baseball America (subscription required) to list him as one of 12 players to watch in the AFL. It has to do with one intriguing pitch that is mystifying hitters.

Sean Paul Liñan’s Impressive Pitch

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The publication heaped praise on Liñan’s changeup, calling it one of the “nastiest changeups in the sport.” The proof is in the data the site tracked. The pitch had a whiff rate of 65%, a rate that makes the pitch nearly unhittable.

The quality of that pitch is reflected in his numbers for 2025, which were collected at three different Dodgers affiliates — Class-A Rancho Cucamonga, High-A Great Lakes and Triple-A Oklahoma City — along with Wilmington. In 19 games, with 15 starts, he went 3-4 with a 3.03 ERA, his lowest since his first pro season in the Dominican Summer League in 2022.

He struck out 106 and walked 33 in 77.1 innings. He allowed batters to hit just .192 against him. But, the opponent batting average went up at Wilmington (.333 in one game) and Oklahoma City (.286 in two games).

Assuming he makes it through the AFL without a setback, he could be in line to start the 2026 campaign at Double-A Harrisburg, or perhaps Triple-A Rochester, depending how his spring training goes. The 20-year-old could get a non-roster invitation to spring training.   

Liñan was an international signee out of Colombia and began his pro career in the Dominican Summer League in 2022. There, he posted an intriguing 4-1 record in 15 games (all in relief) with a 2.08 ERA, 27 strikeouts and 11 walks in 26 innings. That was enough to bring him stateside in 2023, where he played in the Arizona Complex League. Against stiffer competition he went 0-2 with a 4.54 ERA in 12 games (six starts), including 43 strikeouts and 11 walks in 35.2 innings.

The Dodgers started him in the ACL in 2024 but promoted him to Rancho Cucamonga. Combined he went 9-2 with a 4.37 ERA in 19 games, with five starts, as he struck out 93 and walked 26 in 70 innings. Batters hit .257 against him.