Mason McLendon Barnett was originally signed by Royals scout Will Howard...graduated from Cartersville HS (Ga.) in 2019, where he was a two-time Class 5-4A All-Region honoree and Cartersville High School Pitcher of the Year...attended Auburn University from 2020-22, where he struck out 142 batters in 111.1 innings (11.5 strikeouts per nine innings) across 41 appearances (20 starts) over three seasons...made five starts with the Brewster Whitecaps in the Cape Cod League in 2021.
2024
Was acquired by the A’s at the trading deadline with two other players from Kansas City for Lucas Erceg...spent the entire season at the Double-A Level and combined for a 9-8 record, a 4.20 ERA and .701 opponents OPS in 26 games, including 25 starts, with Northwest Arkansas and Midland...Struck out 161 batters in 133.0 innings (10.89 strikeouts per nine innings) and ranked eighth in all of Minor League baseball in strikeouts...Placed second in the Texas League in strikeouts, tied for second in games started, third in innings pitched, fourth in ERA, tied for fourth in wins and fifth in opponents batting average (.240)...Had career highs in every counting category except walks and wild pitches...his ERA and his slashline numbers of .240/.316/.385/.701 were the highest of his three professional seasons...His opponents batting average broke down to .247 (74-for-299) with 10 of his 13 home runs and a .745 OPS against right-handed pitchers compared to .229 (47-for-205) with a .635...OPS against left-handers...Yielded a .220 average with runners in scoring position...opponents were 1-for-8 (.125) with a double and three strikeouts with the bases loaded...As a starter, had a .200 opponents batting average the first time through the order, .250 the second time and .312 with six of his 13 home runs the third time...Combined for a 3-6 record and a 5.62 ERA in 12 starts in his home ballparks...was 6-2 with a 3.11 ERA in 14 games, including 13 starts, on the road...Had a 1.44 ERA in the first inning and a 3.21 ERA over innings 1-4...logged a 6.94 ERA from the fifth inning on...surrendered seven of his 13 home runs in the fifth inning (8.44 ERA)...Was rated as the Royals fourth-best prospect by MLB.com at the time of the trade and was ranked as the A’s sixth-best prospect following the season.
2023
Barnett was the recipient of the 2023 Paul Splittorff Award, given to the top pitcher in the organization, as well as being named an MLB Pipeline Pitcher Prospect of the Year and MiLB.com Organization All-Star... He split the season between High-A Quad Cities and Double-A Northwest Arkansas, where he amassed a 3.30 ERA (42 ER in 114.2 IP) across 23 starts with a Royals Minor League-leading 137 strikeouts (10.8 K/9, 28.8 K%) and a 1.19 WHIP...across his 23 starts, he never allowed more than four earned runs, and following the MLB All-Star break, he went 4-2 with a 2.66 ERA (15 ER in 50.2 IP) over 10 starts... In Quad Cities, he went 4-6 with a 3.18 ERA (29 ER in 82.0 IP), 94 strikeouts (10.3 K/9) and an opponents’ batting average of .203, earning a promotion to Double-A Northwest Arkansas on Aug. 2... He made his Double-A debut on Aug. 8 vs. Wichita and struck out 7 batters over 5.0 innings...each of his next two starts came at Corpus Christi on Aug. 15 and 20, and he combined to cover 9.0 one-run innings with 12 strikeouts and just 6 hits across the two outings.
