In February 2010, Slipper made his Super Rugby debut against the New South Wales Waratahs at Suncorp Stadium in Brisbane.
Slipper was named in the squad for the Australia A national rugby union team's two matches against England in June 2010.
On 12 June 2010, Slipper made his debut for the Australia national rugby union team against England at Perth. He is the 843rd player in history to represent Australia. He quickly became a regular for the national team, playing in all six of Australia's matches in the 2010 Tri Nations Series. Slipper featured in 13 of the Wallabies 14 Tests during 2010.