Nielsen is a hard running midfielder who is currently one of Denmark's most prolific goalscorers.
Ended the domestic season on loan at Wolves, Nielsen has found first team opportunities limited at White Hart Lane despite scoring the winner against Leicester in last season's Worthington Cup final.
As far as the Danes are concerned, he is crucial to their championship hopes.
He failed to win the midfield battle in the first game of the tournament for the Danes against France. It ended in a 3-0 defeat.
Worked hard and battled well with the Dutch midfield until he was substituted in the 61st minute.