[3] In Mercantile club eights Widdicombe contested the Thames Challenge Cup at the Henley Royal Regatta in 2014 and 2015.

[3] Victorian state representation first came for Widdicombe in the 2014 youth eight which contested and won the Noel Wilkinson Trophy at the Interstate Regatta within the Australian Rowing Championships.

He raced in the eight to a fourth place at the World Rowing Cup II in Poznan and in a coxless four at the WRC III in Lucerne.

[10] In the touring party's second regatta of the 2018 season at the Henley Royal Regatta Widdicombe and Campbell Watts achieved the final of the Silver Goblets & Nickalls' Challenge Cup for the men’s pair and took on the champion Croatian brothers Martin and Valent Sinković, Olympic double-sculls champions then presenting their world class credentials as a pair.

[11] The following week at the World Rowing Cup III in Lucerne, Widdicombe stroked the Australian eight to silver medal in a thrilling 0.14 second finish behind Germany.

[14] Widdicombe was selected into the Australian men's eight squad for the 2022 international season and the 2022 World Rowing Championships.

[16] At the Rowing World Cup II in Varese Italy, Widdicombe raced in the Australian men's eight.

[10] For the 2023 World Rowing Championships in Belgrade Serbia, the Australian men's eight was left unchanged and Widdicombe again stroked the crew.