Atlanta United announced on March 9, 2023 that Luke Brennan had signed a Homegrown contract, effective Jan. 1, 2024. Brennan was a member of the club's inaugural Academy class and progressed through Atlanta United's Academy over the past several seasons. He had a breakout year in 2022 when he played over 1,000 minutes for ATL UTD 2. This past season he played with the club's MLS NEXT Pro affiliate and made 25 starts. He scored four goals and added five assists. Brennan received a couple of Short-Term Agreement call-ups to the First Team in 2023, making his MLS debut as a substitute on June 21 against NYCFC.
2023 (Atlanta United / Atlanta United 2): MLS: Made his MLS debut on June 21 vs. NYCFC coming on as a sub. MLS NEXT PRO: Made 25 starts and scored four goals with five assists for ATL UTD 2. Played 2,124 total minutes and had 25 total shots with nine on target.
2022 (Atlanta United 2): USL Championship: Made 27 appearances, 11 starts, for ATL UTD 2 in the USL Championship. Scored two goals and had two assists in his first full season playing with the team. Scored his first professional goal on July 7, 2022 against Birmingham Legion FC.
