The following season, he helped Pisa win the 1984–85 Serie B title, and obtain promotion to Serie A once again. Pisa were relegated once more at the end of the 1985–86 Serie A season. With the Danish national team, Berggreen played an important part in Denmark's first ever qualification for a World Cup tournament. In the penultimate match of the qualification stage in October 1985, Denmark were trailing against Norway by 0–1 at half-time. Ten minutes after the break, Berggreen snapped the ball from a Norwegian defender, and made the assist for Michael Laudrup to tie the game. Berggreen himself went on to score two goals, as Denmark eventually won 5–1. He was included in the Danish squad for the 1986 World Cup, and played three games, before Denmark were once again eliminated by Spain.