Frosinone completed a comeback from 2-0 down to win 3-2 at Cittadella, setting up a Serie B promotion play-off semi-final with Pordenone.
The other semi-final is between Spezia and Chievo, to be played over two legs between August 8 and 12.
Cittadella had surged into a 2-0 lead, Davide Diaw converting a penalty after just five minutes, then doubling his tally in first half stoppages on a classic counter, finished off with his volley.
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