MELBOURNE — Bernard Tomic ground down Jack Sock 7-6(2) 6-3 3-6 6-4 to level Australia's Davis Cup first round tie with the United States at 1-1 in Melbourne on Friday.
The rangy world number 20 hit back for the hosts after John Isner wrapped up the opening singles against Sam Groth 7-6(2) 6-2 6-2 on a sweltering day at Kooyong Lawn Tennis Club.
Flourishing on the grass court installed specially for the World Group encounter, Tomic was cruising toward a comfortable victory before a lapse of concentration led to an early break in the third set.
World number 24 Sock held firm to take the match into a fourth but also dropped his level in the heat and Tomic captured the decisive break in the ninth game.