Guerrero begins his first season with the Ducks and fourth in professional baseball. The pitcher has spent parts of all four seasons (2021-24) in the Milwaukee Brewers organization, reaching the High-A level in each of the past three years. In 98 games (four starts), he went 15-11 with a 5.09 ERA, one complete game, three saves and 178 strikeouts to 87 walks over 173.1 innings. The 23-year-old began 2024 with High-A Wisconsin, recording a win in two games in which he tossed two hitless innings.

The Dominican Republic native split 2023 with Single-A Carolina and High-A Wisconsin. He posted a 3-3 record with a 4.40 ERA, two saves and 57 strikeouts in 57.1 innings across 32 appearances. The righty made 33 appearances combined between the same two teams in 2022, going 5-4 with a 4.84 ERA. He made his pro debut in 2021 with Low-A Carolina, pitching in 31 games (four starts). Guerrero was originally signed by the Brewers as an international free agent in 2020.