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Nationals Pitching Prospect Riley Cornelio Continues Dominant Stretch

Originally posted on Washington Nationals on SI
By JD Andress | Last updated Sep 1, 2025 8:00 AM ET

While the Washington Nationals season has left a lot to be desired, continuing the development in their farm system remains the most important part of the remainder of the 2025 season.

While they ideally have their ace of the future in Mackenzie Gore, finding one to two more pitchers to anchor the rotation of the future is critical before they enter their competitive window. Some of those arms could be a the Major League level already. Luckily for the Nationals, one pitcher in their farm system is having a career year.

Riley Cornelio, a 2022 draft pick, has become one of the best performing pitching prospects in the system, even though he's not considered a Top 30 prospect by MLB Pipeline.

Consistent Development

Riley Cornelio struck out 7 without issuing a walk in 6.0 innings of 3-run ball in @RocRedWings 4-3 win on Saturday night.

He leads Washington's system in ERA (3.08), opp. AVG (.204) and WHIP (1.12) and is 2nd in SO (117). pic.twitter.com/h3o3sZL3mC
— Nationals Player Development (@Nats_PlayerDev) August 31, 2025

In his first full season in the Nationals' minor league system in 2023, Cornelio didn't neccesarily struggle, but he didn't flash either, holding a 4.68 ERA across 22 starts at Class-A Fredericksburg. He did have a solid strikeout to walk ratio. In 92.1 innings he had 86 strikeouts and 49 walks, good for a 1.76 strikeout to walk ratio.

Last season at High-A Wilmington, despite his ERA rising to a 5.56, he held opposing hitters to a .261 average, down from the .285 the season before. He had control issues, finishing with his highest amount of free passes allowed with 65, but kept his strikeout to walk ratio around the same at 1.75.

The seventh-round pick has found his groove this season though. Despite his 6-6 record, he is having the best season of his career as he's pitched for three different affiliates, including Triple-A Rochester. He has a 3.08 ERA in 122.2 innings pitched, and has already set a career record in strikeouts with 117. Most importantly in his development, he has the lowest walks per nine innings of his career at 3.45, a full point lower than his last two seasons.

After his last outing, a six-inning, seven strikeout performance where he earned a 4-3 win, he took over the No. 1 spot in the Nationals' system in ERA (3.08), opponent average (.204), WHIP (1.12) while remaining second in strikeouts (117).

For Cornelio, the success is welcomed, and he seems to have figured out what works for him, which includes keeping his pitch count low. Continuing his approach on the mound, limiting free passes, while striking out opponents at a higher clip than he has experienced remains the key to his success.

Now at Triple-A, Cornelio could find himself on the big league roster with the September call-ups.

This article first appeared on Washington Nationals on SI and was syndicated with permission.

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