The Nigeria international, who joined the White and Blacks at the start of last summer, was a consistent performer for Igor Tudor’s men in his debut season.
Troost-Ekong made 37 appearances across all competitions to help the Stadio Friuli outfit finish 12th on the Serie A table.
The 25-year-old defender continued from where he stopped last term, helping Udinese keep a clean sheet at Dacia Arena.
Rodrigo Becao scored the match-winning goal in the 72nd minute after benefitting from Rodrigo De Pau’s assist.
Algeria international Ismael Bennacer, who joined Milan in the summer, made his debut in the match, replacing Lucas Paqueta in the 76th minute.
Ivorian Franck Kessie was introduced for Fabio Borini in the 60th minute while his compatriot Seko Fofana was a 71st-minute substitute for the Udine-based club.
Troost-Ekong will hope to continue the impressive defensive performances when Udinese try Parma for size on September 1.