A specialist in the rings discipline, Dan Grecu became Romania’s first world champion in artistic gymnastics. Grecu took up gymnastics at an early age and became a multiple time national and Balkan champion during the 1970s. He won his first medal at a major international competition in 1973 with silver at the European Championships after competing at the Olympics in München the year before. His best result came in 1974, winning gold at the World Championships in Varna, Bulgaria, and earning him the honour of being named the Romanian Athlete of the Year.
Grecu continued to have strong results at international competitions, including winning gold at the 1975 European Championships and bronze at the 1976 Montréal Olympics. At the end of the decade he remained consistent at the World Championships, winning bronze in 1978 and silver the following year. Despite suffering with an injury he competed at the 1980 Moskva Olympics where he still managed to finish sixth. The injury to his shoulder and biceps continued to take their toll on Grecu and he retired from the sport to work as the coach of the Romanian national team.