George Kambosos Jr. has four losses against three opponents on his boxing record. For a list of Kambosos Jr.'s best fights, refer to "Best fights of George Kambosos Jr.".
On June 14, 2025 George Kambosos Jr. faced off against Richardson Hitchins in a super-lightweight bout at age 32. He was coming in with a record of 22-4 (10), and Hitchins was 27 years old and with a record of 19-0 (7). Kambosos Jr. lost the fight via 8th-round TKO.
On May 12, 2024 George Kambosos Jr. fought Vasyl Lomachenko in a lightweight world-title fight for the IBF title. Kambosos Jr. was 30 years old and with a record of 21-3 (10), and Lomachenko was 36 years old and with a record of 17-3 (11). Kambosos Jr. lost the fight via 11th-round TKO.
On October 16, 2022 George Kambosos Jr. fought Devin Haney in a lightweight world-title fight for Haney's WBA (Super), WBC, IBF, WBO and The Ring titles. Kambosos Jr. was 29 years old and with a record of 20-2 (10), and Haney was 23 years old and with a record of 28-0 (15). Kambosos Jr. lost the fight via 12-round unanimous decision.
On June 5, 2022 George Kambosos Jr. met Devin Haney in a lightweight () world-title defense fight. Kambosos Jr. was 28 years old and with a record of 20-1 (10), and Haney was 23 years old and with a record of 27-0 (15). Kambosos Jr. lost the fight via 12-round unanimous decision and lost the titles.
