Napoli lost their final pre-season friendly to Girona in a match played beneath a deluge at the Stadio Patini in Castel di Sangro.
Donny van de Beek gave the Spanish side the lead midway through the first half.
With the second half drawing to a close, Amir Rrahmani struck the woodwork from a corner before Toni Villa slid in make it 2-0.
The Azzurri will now turn their attentions to next Saturday's Coppa Italia clash with Modena at the Stadio Maradona.
Napoli 0-2 Girona (0-1)
Scorers: Van de Beek 23, Villa 83.
Napoli: Meret; Di Lorenzo, Rrahmani, Buongiorno, Mazzocchi (Zerbin 58), Lobotka, Anguissa, Spinazzola (Marin 78), Politano (Ngonge 89), Kvaratskhelia, Raspadori (Simeone 78).
Coach: Conte.
Girona: Gazzaniga, Arnau (Antal 85), David Lopez (Roca 85), Blind, Frances, Van de Beek (Stuani 65), Yangel Herrera (Juanpe 72), Ivan Martin, Portu (Villa 72), Bryan Gil (Minsu 85), Valery (Almena 65).
Coach: Michel.
Referee: Scatena (Avezzano).
