The Uruguay international was pleased with his side's performance in Wednesday's 2-0 victory at Chievo, and has now set his sights on a successful league campaign
The left-back joined the 18-time Italian champions from Porto in the summer transfer window, for a fee reported to be in the region of €13.5 million [£10.7m], and does not see why they cannot reclaim their grip on the Scudetto.
"If I win the Scudetto, I will cut my hair," joked Pereira after his midweek success. "We believe we can win the Scudetto.
"Against Chievo, you could see our true colours. We did well to react immediately after the bad defeat against Siena."
The Nerazzurri lie four points from the summit of Serie A, in fourth place, and are next in action against Fiorentina at the Giuseppe Meazza on Sunday.