Frosinone has been relegated from Serie A after surrendering a two-goal lead to draw 2-2 at Sassuolo; Marco Baroni's side needed to win at MAPEI Stadium to have any hopes of avoiding the drop to Serie B.
And they led 2-0 at the break, captain Paolo Sammarco having opened the scoring before Luca Paganini struck.
Frosinone, who have only won five times in the league this season, collapsed after the interval, however. Sassuolo hit back through Gianmarco Ferrari in the 66th minute and 11 minutes later Jeremie Boga levelled.
Baroni's men could not find a late winner and they join Chievo in being relegated from Serie A.
Empoli, in 18th, claimed a 1-0 win at home to Fiorentina, secured thanks to a 54th-minute Diego Farias goal that moved them within two points of 17th-placed Udinese.
At the other end of the table on Sunday, Atalanta won 3-1 at Lazio to move a point behind third-placed Inter.
They occupy the final Champions League qualification place and sit four points clear of Roma, with the Giallorossi away to Genoa later in the day.