Complex sentence: Whilst playing for Vienna in 2007, Pusic was called up to the Austrian U- 20 squad in preparation for the U- 20 World Cup in Canada and played his first and, to date, only international game for the Austrian U- 20 team.
Split into simpler sentences: Whilst playing for Vienna in 2007, Pusic was called up to the Austrian U- 20 squad in preparation for the U- 20 World Cup in Canada. It was during this preparation, he played his first and, to date, only international game for the Austrian U- 20 team.