Sassuolo marked their debut in the Europa League with a 3-0 win over seasoned campaigners Athletic Bilbao.
The Serie A side left all their scoring until the final half-hour but the romped to victory with goals from Pol Lirola, Gregoire Defrel and Matteo Politano.
Bilbao, who had won four out of their five last European away game, began strongly with Yeray Alvarez (twice), Munain and Benat all have chances in the first half.
Sassuolo survived until the break and despite coming under more pressure rode their luck until the hour mark when Lirola fired them in front. He went on a brilliant, mazy run before opening his body and curling in, making good of Davide Biondini's pass.
The goal energised the home side and with 15 minutes remaining Defrel doubled their advantage, cashing in after a lapse backpass put him through on goal.
Frenchman Defrel then teed up Politano for a left-footed shot from outside the box to wrap things up in the 82nd minute and secure a memorable night in the Italian club's history.