Answer by taking a quote from the following article:

Allan Rodenkam Simonsen (born 15 December 1952) is a former Danish footballer and manager. He most prominently played as a forward for German Bundesliga club Borussia Monchengladbach, winning the 1975 and 1979 UEFA Cups, as well as for Barcelona from Spain, winning the 1982 Cup Winners' Cup. Simonsen is the only footballer to have scored in the European Cup, UEFA Cup, and Cup Winners' Cup finals. Simonsen was named 1977 European Footballer of the Year.

He debuted for the Danish national team under manager Rudi Strittich in the July 1972 friendly match against Iceland. He scored two goals as Denmark won 5-2, and Simonsen was included in the Danish squad for the 1972 Summer Olympics. At the Olympics, he scored three goals in the first three matches to help Denmark advance beyond the first group stage. In the second group stage, Simonsen ran out of steam and he was substituted at half time in two of the last three games as Denmark were eliminated.  He played a crucial part for the Danish national team under manager Sepp Piontek, in Denmark's qualifying campaign for the 1984 European Championship. Denmark led their qualifying group with a single point over second placed England before the two teams met at England's home ground Wembley Stadium in September 1983. Simonsen scored one of the most important Danish goals ever, as he converted a penalty kick against English goalkeeper Peter Shilton. The 1-0 win eventually secured the Danish national team qualification for their first international tournament since the 1972 Olympic Games, and the first European Championship participation since the 1964 tournament. It effectively ended England's hopes of qualification for the tournament. He subsequently finished third in the vote for the 1983 European Footballer of the Year award.  The 1984 European Championship main tournament was a short experience for Simonsen, as he broke his leg in a challenge by Yvon Le Roux in Denmark's first match against France. Even without Simonsen, Denmark reached the semi-finals. He was once more a part of the Danish national team at the 1986 World Cup, Denmark's first World Cup participation. He only played a single match at the tournament, coming on as a substitute against West Germany, as younger players had surpassed him. He played a farewell match against Germany in September 1986 before ending his national team career.  Simonsen played a total 55 games for the Danish national team and scored 20 goals, according to the Danish Football Association. However, some sources chose to include Simonsen's appearance in a February 1981 charity match, to tally his national team career as 21 goals in 56 games. The match was Italy vs. Europe for the benefit of the Irpinia earthquake victims. Simonsen started the game, scored a goal, and was substituted at half time as Europe won 3-0.

Did he play for any other team?
He played a farewell match against Germany in September 1986 before ending his national team career.