Right half Nils Middelboe, born in Brunnby, Sweden, was a Danish amateur athlete and footballer as well as a football referee and leader. He represented the Denmark national football team at the 1908, 1912 and 1920 Summer Olympics, winning silver medals in 1908 and 1912. He was the first ever goalscorer for the Danish national football team, when he scored in Denmark’s debut game at the 1908 Summer Olympics. In 1913, he moved abroad to play for English club Chelsea, and became the first foreign player to ever represent the club. Middelboe made his senior debut for Kjøbenhavns Boldklub (KB) in 1903, at the age of 16. At KB, he played alongside his older brothers Einar Middelboe and Kristian Middelboe, of whom Kristian also played for the Danish national team. From 1904 to 1913 Nils won five KBU football championships with KB, while he also excelled in athletics competitions. He was a Danish triple jump and 4 x 100 metres relay champion, and he set Danish records in the 800 metres (with a time of 2:05.2) and triple jump (13.29 m).
Occupying the half back role, he won silver medals with Denmark in both the 1908 and 1912 Olympic Games, the latter as captain of the side. His goal against France in 1908 was the first ever goal scored by an official national team in Olympic football. Middelboe won his 11th cap for Denmark in a friendly against Sweden, at the time this made him Denmark’s all-time leading appearance maker. In all, he played 15 matches and scored 7 goals for the Danish national team from 1908 to 1920. Interestingly, the three times Middelboe played for his country while at Chelsea, he always represented KB, as opposed to Chelsea.
Nils Middelboe is renowned as the first non-British international to play for Chelsea, during his stint at the club between 1913 and 1923. Originally he had signed for Newcastle United, however with the permission of the Newcastle Directors, he switched to Chelsea. He made his Football League debut against Derby County at Stamford Bridge on 15th November 1913 – a 2-1 win for Chelsea. As a show of faith from the players, he was appointed captain despite never having previously played for the Chelsea first team. In all, he played 175 matches for Chelsea until his final appearance in January 1922, 41 of these in the Football League and 5 in the FA Cup.
After his days at Chelsea, he played for the amateur sides of The Corinthians and The Casuals until 1926. In 1929 he was appointed a Director of the Division Three (South) club Clapton Orient. He returned to Denmark in 1936. It was through Middelboe’s contacts in English football, that English coach Edward Magner was hired to coach the Danish national team in 1939. As an interpreter, Middelboe mediated Magner’s tactical instructions on the modern WM formation to the team, a formation Middelboe himself was a known critic of. As a coach for KB, he led the team to the Danish Championship in 1940. In April 1946, Chelsea played KB in a friendly, arranged to celebrate that club’s 70th anniversary. The chairman of KB announced that, owing to Middelboe’s “long and happy association” with Chelsea, there was no other club they would rather be facing.