Triolo made his professional debut with the
West Virginia Black Bears of the
Low–A New York–Penn League where he batted .239/ 314/.389 with two home runs and 34 RBIs over sixty games, in which he played 41 games at third base and 17 games at shortstop. He did not play a game in 2020 due to the cancellation of the minor league season because of the
COVID-19 pandemic. He played the 2021 season with the
Greensboro Grasshoppers of the
High-A East,
slashing .304/.369/.480 with 15 home runs, 42 RBIs, 29 doubles, and 25 stolen bases over 108 games, in which he played 102 games at third base and five games at shortstop. He was awarded a Minor League Gold Glove for his defense at third base. He was assigned to the
Altoona Curve of the
Double-A Eastern League for the 2022 season. Triolo was optioned to the
Indianapolis Indians of the
Triple-A International League to begin the 2023 season. On March 27, 2023, it was announced that Triolo would undergo surgery to address a fractured hamate bone in one of his wrists and miss multiple months in recovery. Once he returned, Triolo played in 41 games split between the Single–A
Bradenton Marauders and Indianapolis, hitting a cumulative .309/.412/.463 with one home run, 24 RBI, and eight stolen bases while playing 32 games at third base, 16 games at shortstop, nine games at second base, and three games at first base. He hit his first MLB home run on August 13, a pinch-hit three run home run at
PNC Park, helping lead the Pirates to a 4-2 win over the
Cincinnati Reds. Triolo appeared in 54 games for the Pirates during the 2023 season and batted .298/.388/.398 with three home runs and 21 RBI over 181 at-bats. The Pirates named Triolo to his first
Opening Day roster for the 2024 season, and Pirates manager
Derek Shelton announced he would be the team's starting second baseman. He spent the entirety of the season with Pittsburgh and batted .216/.296/.315 with nine home runs and 46 RBI in 394 at-bats. He played 61 games at third base, 47 at second base, nine at shortstop, nine at first base, and one in right field. His defensive efforts earned him the National League
Gold Glove Award for utilitymen. Triolo began the 2025 season on the injured list with a lumbar spine strain. He was activated on April 16 and returned to the Pirates. In July, he was optioned to Indianapolis after hitting .158 over 55 games with Pittsburgh. He was promoted back to the Pirates on August 1. Across 107 games played with the Pirates, Triolo hit .227 with 7 home runs, 24 RBI, and 13 stolen bases. ==References==