Seven months later, Jensen joined Denmark's under-20 team, competing in Division I of the 2010 World Junior Championships, held in Megeve and Saint-Gervais, France. Once again the youngest player on the team, he tied for third among Danish players in scoring with five points (three goals and two assists) over five games, while recording a team-leading 19 shots on goal. Denmark finished second in Pool A, missing out on a promotion to the 2011 tournament's main division by one win.