Jonathan Arturo Aro (born October 10, 1990) is a Dominican professional baseball pitcher for El ÃÂguila de Veracruz of the Mexican League. He has previously played in Major League Baseball (MLB) for the Boston Red Sox and Seattle Mariners. He made his MLB debut in 2015.
The Boston Red Sox signed Aro as an international free agent on June 6, 2011. He grew up in the Dominican Republic idolizing Red Sox legend and Hall of Famer Pedro MartÃÂnez. His pitching repertoire includes a 91âÂÂ93 mph fastball which occasionally reaches 95 mph, as well as an 83âÂÂ85 mph changeup and a slurve at 78âÂÂ81 mph with a short, 11-to-5 break, throwing most of them for strikes.
Aro made a fast ascent in the Boston Minor League system in a span of four years. After spending a full season each with the Dominican Summer League Red Sox, Gulf Coast League Red Sox, and Lowell Spinners from 2011 through 2013, he spent 2014 with the Salem Red Sox and the Greenville Drive. Besides, he was named a SoxProspects.com All-Star in both 2013 and 2014, and was also honored as South Atlantic League All-Star in the 2014 season, after finishing with a record of 1âÂÂ3 and a 2.16 ERA and 10 saves in 25 games, including 74 strikeouts and 22 walks in innings pitched. In his two stints, Aro went 3âÂÂ8 with a 2.16 ERA and eight saves in innings of work, setting the second lowest ERA in the Red Sox minors system in a minimum of 80 innings pitched, being surpassed only by Brian Johnson (2.13).
Aro joined the Portland Sea Dogs bullpen in 2015, where he posted a 3âÂÂ2 record with a 2.28 ERA in eight appearances, striking out 19 and walking eight in innings. He then appeared in his fourth level in less than ten months, after being promoted to the Pawtucket Red Sox in May 2015. On June 25, Aro earned a promotion to the Boston Red Sox. He was optioned July 2 after three appearances, then was recalled in September, making six total appearances with Boston for the season while recording an 0âÂÂ1 record with 6.97 ERA. Aro was also the recipient of the Red Sox' Lou Gorman Award.
On December 7, 2015, the Red Sox traded Aro and Wade Miley to the Seattle Mariners for Roenis ElÃÂas and Carson Smith. On January 26, 2017, Aro was designated for assignment by the Mariners. After clearing waivers, Aro was outrighted to the Triple-A Tacoma Rainiers on February 1. On April 24, Aro was suspended 50 games by MLB for a drug of abuse. In 25 appearances for Tacoma, he posted a 6âÂÂ1 record and 3.16 ERA with 48 strikeouts across innings pitched. Aro elected free agency following the season on November 6.
On November 27, 2017, Aro signed a minor league contract with the San Diego Padres. In 38 relief outings for the TripleâÂÂA El Paso Chihuahuas, he recorded a 3.68 ERA with 36 strikeouts across 44 innings pitched. Aro elected free agency following the season on November 2, 2018.
On January 18, 2019, Aro signed a minor league contract with the Atlanta Braves. He made 31 appearances split between the DoubleâÂÂA Mississippi Braves and TripleâÂÂA Gwinnett Stripers, accumulating a 6âÂÂ3 record and 3.53 ERA with 40 strikeouts across innings pitched. Aro elected free agency following the season on November 4.
On January 29, 2020, Aro signed with the Guerreros de Oaxaca of the Mexican League. Aro did not play in a game in 2020 due to the cancellation of the Mexican League season because of the COVID-19 pandemic. He was released by the Guerreros on November 18. On March 5, 2021, Aro re-signed with Oaxaca. Aro registered a 11.72 ERA with 5 strikeouts in 7 games for Oaxaca before being released on June 15.
On June 19, 2021, Aro signed with the Mariachis de Guadalajara of the Mexican League. In 19 appearances for Guadalajara, Aro registered a 2.95 ERA with 17 strikeouts in innings of work.
On March 16, 2022, Aro signed a minor league contract with the Los Angeles Angels organization. Aro made 40 appearances (7 starts) for the Triple-A Salt Lake Bees, working to a 4âÂÂ7 record and 6.03 ERA with 51 strikeouts and 3 saves in innings pitched. He elected free agency following the season on November 10.
On February 21, 2023, Aro signed with the Mariachis de Guadalajara of the Mexican League. In 46 appearances for Guadalajara, he posted a 4âÂÂ2 record and 2.51 ERA with 44 strikeouts and 15 saves across innings of relief.
On February 14, 2024, Aro signed with the Charros de Jalisco of the Mexican League. He made 17 appearances for Jalisco, struggling to an 0âÂÂ3 record and 8.10 ERA with 13 strikeouts and 6 saves over innings pitched.
Aro made 11 appearances for Jalisco in 2025, but struggled to a 9.22 ERA with nine strikeouts across innings pitched.
On June 1, 2025, Aro was traded to the Guerreros de Oaxaca of the Mexican League. In 11 appearances for Oaxaca, he struggled to a 0-1 record and 13.50 ERA with six strikeouts over eight innings of work. Aro elected free agency on July 2.
On July 3, 2025, Aro signed with El ÃÂguila de Veracruz of the Mexican League. In 17 games he threw 17 innings of relief going 0-0 with a 1.06 ERA and 15 strikeouts.