On November 24, 2015, Frías signed with the Arizona Diamondbacks as an international free agent.[1] He made his professional debut in 2016 with the Dominican Summer League Diamondbacks, where he posted a 3.83 ERA with 47 strikeouts in 13 games (11 starts). Frías missed the entirety of the 2017 campaign as the result of an injury.[2]
Frías returned to action in 2018 with the rookie–level Arizona League Diamondbacks and Low–A Hillsboro Hops. In 14 games (13 starts) split between the two affiliates, he accumulated a 1–5 record and 2.80 ERA with 58 strikeouts across 54+2⁄3 innings pitched.[3] Frías split 2019 between Hillsboro and the Single–A Kane County Cougars, registering a 6–4 record and 2.83 ERA with 101 strikeouts in 76+1⁄3 innings pitched across 16 starts.[4]
Frías did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[5] On November 20, 2020, the Diamondbacks added Frías to their 40-man roster to protect him from the Rule 5 draft.[6]
On February 22, 2021, Frías was placed on the reserve/COVID-19 list as he continued to recover from the virus.[7] He was called up for his MLB debut on September 19.[8] In 3 games during his rookie campaign, Frías recorded a 2.70 ERA with 3 strikeouts across 3+1⁄3 innings pitched.
Frías was optioned to the Triple-A Reno Aces to begin the 2023 season.[9] He made 29 appearances for Arizona, posting a 4.06 ERA with 26 strikeouts across 31 innings pitched.
In 7 appearances for the Diamondbacks in 2024, Frías struggled to a 9.95 ERA with 7 strikeouts across 6+1⁄3 innings pitched. On August 8, 2024, Frías was designated for assignment following the acquisition of Andrew Knizner.[10]
Toronto Blue Jays
On August 10, 2024, Frías was claimed off waivers by the Toronto Blue Jays.[11] In 4 games for the Blue Jays, he struggled to a 21.60 ERA with 5 strikeouts over 3+1⁄3 innings pitched. On November 4, Frías was removed from the 40–man roster and sent outright to the Triple–A Buffalo Bisons, but he rejected the assignment and elected free agency.[12]
