Five minutes into added time, Lautaro Martinez unleashed a low shot that Udinese goalkeeper Maduka Okoye managed to tip onto the post but Frattesi pounced to slot home the rebound.

Runaway leaders Inter are 14 points clear of second-placed AC Milan, boasting 82 points with seven matches remaining. Udinese are 15th with 28, just two points above the drop zone.

Udinese had stunned the visitors five minutes before the break when poor communication between Inter’s defence and static keeper Yann Sommer allowed a weak deflected cross from Lazar Samardzic to find its way into the bottom corner.

Hakan Calhanoglu levelled for Inter with a penalty in the 55th minute after Okoye collided with Marcus Thurman in an aerial challenge before Frattesi netted the late winner.