Australian youngster Jordan Thompson has given Australia the perfect start in the Davis Cup quarter-final tie against the US, with an upset four-set win over Jack Sock.

Thompson won the match 6-3, 6-7, 7-6, 6-4 at Pat Rafter Arena, with Davis Cup captain, Lleyton Hewitt, typically vocal and passionate on the side linesย during the win.

Thompson is undefeated at Davis Cup level, after he won both his singles matches against the Czech Republic in February this year.

Nick Kyrgios is next to take to the court, with the world No.13 facing off with 23rd-ranked big serving American, John Isner.

Sam Groth and John Peers will then play doubles on Saturday against Steve Johnson and Sam Querry.