Watch: Locatelli's screamer leads AC Milan comeback vs. Sassuolo

A spirited comeback by AC Milan on Sunday took its most dramatic turn when 18-year-old substitute Manuel Locatelli scorched an equaliser against Sassuolo - the third goal in an eventual 4-3 win for the Rossoneri.

Replacing unpopular captain Riccardo Montolivo in the 60th minute, Locatelli signaled a change in a match that looked likely to escape the host.

Milan manager Vincenzo Montella was sent off at half-time for dissent, and his side proceeded to fall 3-1 behind Sassuolo after several lapses in defence.

But a smart run by half-time substitute M'Baye Niang earned a penalty that provided the foundation for the fightback.

Carlos Bacca converted the spot-kick, 18-year-old Locatelli hammered a maiden Serie A goal, and defender Gabriel Paletta towered over his marker to deliver an unbelievable victory.

It's the latest high-wire act in a burgeoning rivalry between these two clubs, with Sassoulo and Milan taking four wins each in the eight games played since the Neroverdi's promotion in 2013.