Piacenza were relegated to Lega Pro for the first time in 20 years after a dramatic 2-2 draw with Albinoleffe.
The sides were all square from the first leg and it looked as if Albinoleffe had it made when they went 2-0 up by half-time.
Girasole completed a well-worked free kick to open the scoring, then Grossi's left-foot strike doubled their advantage.
Piacenza fought back admirably after the break when Cacia both earned and converted a penalty.
Graffiedi completed the comeback by pouncing on a defensive error to make it 2-2.
However, away goals do not count in the Serie B play-offs, so with everything square after two legs it went down to the team with the superior record during the season.
Albinoleffe finished higher up the table, so they remain in Serie B and Piacenza go down to Lega Pro after two decades.
Albinoleffe 2-2 Piacenza
Scorers: Girasole 10 (A), Grossi 34 (A), Cacia pen 49 (P), Graffiedi 77 (P)