Despite the loss, Sassuolo had 54 per cent possession as both sides created seven chances.
Vlahovic’s first goal came in the 15th minute via a shot from just outside the box that Sassuolo goalkeeper Andrea Consigli got a hand on but couldn’t stop.
He had his second in the 37th with a freekick that went in off the underside of the crossbar.
Substitute Federico Chiesa was also on target, sealing the game in the 89th minute with a slightly deflected shot that went straight at Consigli but went in after hitting his body.
Overall, it was a night to forget for the Sassuolo keeper.
Juve are second with 49 points from 20 games.
