Whatever Spalletti and his boys were up to since that announcement has worked wonders as the Naples side thrashed Sassuolo to keep their Champions League hopes alive.
Napoli went ahead within the first seven minutes of the encounter as commanding Senegalese defender Kalidou Koulibaly rose highest to meet Lorenzo Insigne's corner and emphatically headed the ball home.
Not one to be outdone, Osimhen soon scored a header of his own. In the 15th minute, the Super Eagles striker headed home from close range after yet another beautiful Insigne delivery.
Napoli soon scored again with Hirving Lozano unleashing a venomous shot straight into the bottom left corner, and Sassuolo were sinking without a trace.
The home side was firing on all cylinders, and when Belgian forward Dries Mertens made a late run into the box and controlled a brilliant pass, there was no surprise when he calmly finished past the goalkeeper to give Napoli a 4-0 lead in the first 20 minutes!
With the game settled, Napoli confidently stroked the ball across the park and nearly added a fifth in the 38th minute when Osimhen tried a curler from the edge of the box but saw his effort narrowly miss the target.
Napoli showed no signs of slowing down in the second half and 10 minutes after the restart, they got another one. Mertens reacted quickly to control and score a tidy finish to put the home side five goals ahead.
Napoli were not done and in the 80th minute Amir Rrahmani clinically fired a low shot into the bottom corner after receiving a good pass from Fabian Ruiz inside the box .
In what could only be regarded as a consolation goal, Sassuolo grabbed one back in the dying embers of the game. Maxime Lopez kept his composure when he found himself one-on-one with David Ospina and the youngster calmly slotted the ball past the former Arsenal goalkeeper.
With that emphatic win Napoli still keep their slim hopes for a Serie A title alive while all but confirming their spot in next season's UEFA Champions League.