Politano's goal was the difference as Sassuolo stay up for another season.
“It's an important goal for me and for everyone, as finally we have our safety in hand," the forward told Sky Sport Italia.
“It's not the season we wanted, it didn't go as planned, but we are glad that we'll be in Serie A for another season.
“Once we realised that we had to fight to the end for safety, after the defeat to Crotone, we all said we couldn't carry on like that and had to change gear."
Politano was close to joining Napoli in January and added: “Whether I stay depends on the club, not on me."