 Complete the following phrase:  At Sampdoria he formed a prolific strike partnership with teammate and childhood friend Roberto Mancini, earning the nickname The Goal Twins I Gemelli del Gol, in Italian. With Vialli at his best, Sampdoria had the most successful era in its history. They won their first ever Serie A championship in the 199091 season, in which Vialli was league top scorer with 19 goals  celebrating many of his goals with a backflip, including one against Inter  one UEFA Cup Winners Cup 1990  where he scored both goals in the 20 win over Anderlecht in the final once again finishing the tournament as top-scorer, and three Italian Cups in 1985, 1988 and 1989, also setting a record of 13 goals in a single edition of the Coppa Italia during his time at the club. They also won a Supercoppa Italiana, and reached the final of the UEFA Supercup, and the European Cup 