Cionel Félix Pérez Viera (born April 21, 1996) is a Cuban professional baseball pitcher for the Washington Nationals of Major League Baseball (MLB). He has previously played in MLB for the Houston Astros, Cincinnati Reds, and Baltimore Orioles. He signed with the Astros as an international free agent in 2016, and made his MLB debut with them in 2018.
Pérez played two seasons for Matanzas of the Cuban National Series. In September 2016, he signed a $5.15 million contract with the Houston Astros as an international free agent. The contract was voided in October due an issue in his physical. On December 9, Pérez agreed to a new deal with the Astros worth $2 million.
Pérez made his professional debut with the Single-A Quad Cities River Bandits in 2017. He was promoted later that season to the High-A Buies Creek Astros and Double-A Corpus Christi Hooks. In 21 total games (16 starts) between the three clubs, he posted a 6âÂÂ4 record and 4.13 ERA with a 1.29 WHIP. The Astros added Pérez to their 40-man roster after the season, in order to protect him from the Rule 5 draft. Pérez made his major league debut on July 11, 2018. In 2019, he played for the rookie-level Gulf Coast League Astros, High-A Fayetteville Woodpeckers, and Triple-A Round Rock Express, going 3âÂÂ1 with a 4.94 ERA and 58 strikeouts over innings. Pérez appeared in 5 games for the Astros in 2019, going 1âÂÂ1 with a 10.00 ERA and 7 strikeouts over 9 innings. In 2020 for Houston, Pérez made 7 appearances, registering a 2.84 ERA with 8 strikeouts in innings of work.
On January 23, 2021, the Astros traded Pérez to the Cincinnati Reds in exchange for Luke Berryhill. Pérez made 25 appearances for Cincinnati in 2021, compiling a 1âÂÂ2 record and 6.38 ERA with 25 strikeouts across 24 innings pitched.
On November 24, 2021, Pérez was claimed off waivers by the Baltimore Orioles. On June 12, 2022, Pérez recorded his first career save in a 10âÂÂ7 win over the Kansas City Royals. Pérez made 66 appearances for Baltimore in 2022, pitching to a stellar 7âÂÂ1 record and 1.40 ERA with 55 strikeouts in innings pitched.
Perez appeared in 65 contests for the Orioles during the 2023 campaign, compiling a 4âÂÂ2 record and 3.54 ERA with 44 strikeouts and 3 saves across innings of work. He took a step back in 2024, working to a 4.53 ERA with 46 strikeouts and 2 saves across 62 relief appearances.
Pérez made 19 appearances for Baltimore in 2025, but struggled to an 8.31 ERA with 21 strikeouts across innings pitched. Pérez was designated for assignment by the Orioles following the promotion of Yaramil Hiraldo on May 24. He cleared waivers and was sent outright to the Triple-A Norfolk Tides on May 31. In 21 appearances for Norfolk, he struggled to a 1âÂÂ2 record and 6.85 ERA with 23 strikeouts across innings pitched. Pérez elected free agency on September 29.
On February 14, 2026, Pérez signed a minor league contract with the Washington Nationals. On March 23, the Nationals selected Pérez's contract after he made the team's Opening Day roster.
Perez is married and has two children.