Isaac Coffie'sGenoa utterly annihilated Juventus in the first half and sent the leaders crashing to a 3-1 defeat on Sunday.
The Ghanaian midfielder played the full 90 minutes as Giovanni Simeone netted twice to help Genoa to a shock the Old Ladies at the Stadio Luigi Ferra.
Coffie did a wonderful job in protecting his back three with a strong defensive performance. He looked particularly impressive after the break, with the only blemish being the free-kick that he gave away and which resulted in Pjanic's goal.
Genoa made a flying start and went 1-0 up after some shocking defending from Leonardo Bonucci sent Luca Rigoni clean through on goal. Gianluigi Buffon did well to deny the winger but the rebound eventually fell to Simeone, who beat the goalkeeper at the second attempt.
Things then went from bad to worse for Juve as Simeone doubled his side's lead with a close-range header from Darko Lazovic's pinpoint cross.
It was all Genoa before the interval and Juve fell 3-0 down before the half-hour mark. Nicolas Burdisso headed the ball into Rigoni's path and the winger steered an attempt against the underside of the bar, before the ball crossed the goalline via the Brazilian's thigh.
Pjanic pulled one back for Juventus after scoring a magnificent free-kick.