Ivo Karlovic survived a scare before edging out Jack Sock at the BNP Paribas Open at Indian Wells.
Karlovic, the former world No 14, needed to save a match point before finally beating the American wild card 3-6 7-6 (10-8) 6-2.
Karlovic will be joined in the second round by fellow qualifiers Matthew Ebden and Philipp Petzschner.
Ebden toppled Andrey Kuznetsov 6-3 4-6 6-4, while Petzschner registered a routine 6-4 6-4 win over Dmitry Tursunov.
James Blake was no match for Robin Haase as the American raced to a 6-3 6-4 win, while Nikolay Davydenko overcame Paul-Henri Mathieu 7-6 (7-1) 6-2.
Marinko Matosevic will face 14th seed Juan Monaco in the second round after he breezed past Tommy Robredo 7-5 6-2, while Pablo Andujar recovered from a slow start to see off Steve Johnson 2-6 6-1 6-4.