Born in Aarhus, Denmark on May 10, 1997. He started playing handball at the age of 10 for his hometown club, and he already stood out as great prospect in his country as a youth. In fact, he made his debut at only 17 years old with Aarhus GF. 2014 saw him called up to the Under-18 Danish team, which finished fourth in the European Championship. Emil was named best goalkeeper and included in the tournament's All-Star team.
He signed for the Danish side Skjern Handball in summer 2017, where he remained until his transfer to Nantes in 2019. Nielsen enjoyed great success in northeast France, establishing himself as one of the most promising keepers in the world, lifting trophies with the French side.
Emil Nielsen is keeper with great shot anticipation and reflexes when reacting to his opponent's position. He is also very quick between the posts despite his size and brings a lot of assurance to his defence. He is also known for showing character at significant moments.