Competing for Great Britain, Arnott came through a tough semi to reach the T47 100m final at the IPC European Athletics Championships in Grosseto, Italy.
The City of Plymouth athlete, who has limited movement in his left shoulder due to Erbs Palsy, clocked 11.58 seconds in the morning session.
the final, the competitors found themselves running into a head win and times were slower with 19-year-old Arnott crossing in 11.78. He was just five hundredths of a second off finishing fourth. However, he was the first T46 athlete to finish.
The race was won by Poland’s Michal Derus, who clocked 11.14. Russians Aleksei Kotlov and Vadim Trunov were second and third respectively in 11.38 and 11.56.