Rosario Central Buonanotte is a product of the youth academy of
Rosario Central since the age of ten. He made his professional debut as a substitute for Rosario Central against
Arsenal de Sarandí on 11 February 2022. In a
Copa Argentina penalty shoot-out victory against on 13 May 2022, he scored the game-winning penalty. The next day, on 14 May 2022, Buonanotte signed his first professional contract with Rosario Central. He scored his first senior goal in a 1–0
Argentine Primera División victory against
Sarmiento on 8 July 2022.
Brighton & Hove Albion On 1 January 2023, Buonanotte joined the
academy of
Premier League club
Brighton & Hove Albion for an estimated fee of £5.3m, with an additional £5.3m dependent on objectives being met. He made his debut for the Seagulls on 4 February, coming on as a 75th minute substitute replacing
Tariq Lamptey as Brighton went on to beat
AFC Bournemouth with a 87th-minute
Kaoru Mitoma goal. Buonanotte made his first start for Brighton on 28 February, playing 69 minutes of the 1–0 away victory against
Stoke City of the
Championship with Brighton advancing to the
FA Cup quarter-finals. Buonanotte claimed an assist four days later, setting up
Danny Welbeck's strike, the last of the game in the 4–0 home victory against
West Ham United. The then-18-year-old Argentine gained his first Premier League start on 26 April, where he scored his first goal for the club, opening the score in the eventual 3–1 away loss against
Nottingham Forest.
Loan spells On 10 August 2024, Buonanotte went on loan to fellow Premier League club
Leicester City for the 2024–25 season. He made his Leicester debut on 19 August 2024 in a 1–1 home draw against
Tottenham Hotspur. His first goal came on 31 August in a 2–1 defeat against
Aston Villa. On 1 September 2025, Buonanotte joined
Chelsea on a season-long loan. He made his Chelsea debut on 13 September in a 2–2 home draw against
Brentford. He scored his first and only Chelsea goal in a 2–1 victory over
Lincoln City in the
EFL Cup. Buonanotte returned to Brighton on 15 January 2026, and subsequently joined
Leeds United on a different loan deal until the end of the season. ==International career==