Under new management, Atalanta comfortably won Group A of Serie C1 in 1982, returning to Serie B the next season and then to Serie A in 1984, where it would remain until 1987. Atalanta reached its second Coppa Italia final in 1987, though lost 4–0 to Napoli over two legs. As Napoli also won Serie A that season and therefore qualified for the European Cup, Atalanta qualified for its second European Cup Winners' Cup. This was a turning point for the club; Emiliano Mondonico was appointed as coach and the club would achieve promotion after only one season in Serie B. In the Cup Winners' Cup, Atalanta lost its first match against Welsh club Merthyr Tydfil, but won the return fixture and went on to reach the semi-finals, where it would be eliminated 4–2 on aggregate by Belgian club K.V. Mechelen, who would eventually win the tournament. In doing so, Atalanta achieved the best finish in a UEFA competition of a club playing outside its country's top flight league. With a sixth-place finish in the 1988–89 Serie A, Atalanta qualified for its first UEFA Cup, though was eliminated by Russian club Spartak Moscow in the first round. Atalanta then finished seventh in the 1989–90 Serie A and reached the quarterfinals of the 1990–91 UEFA Cup, losing to local rival and eventual winner Internazionale.