Dusan Lajovic of Serbia ousted Great Britain's Andy Murray in straight sets Wednesday in the first round of the Miami Open.
Lajovic, ranked 76th in the world, won 6-4, 7-5 in 96 minutes. He converted all three of his break points, while Murray was only 1 of 3.
Murray, who was No. 1 in the rankings for 41 weeks, including at the end of 2016, said he expected better after winning two matches in the BNP Paribas Open in Indian Wells, Calif., earlier this month.
"I served pretty well, but the rest of the game was a bit of a problem today. Didn't really return that well, made a number of errors that obviously I wouldn't expect to be making," Murray said after the match.
"I didn't really feel like I moved particularly well, which is really important for me, something I've been doing very well actually in most of the matches this year. So that was probably the thing."
In a matchup of Americans late Wednesday, Emiliano Nava needed tiebreakers in each set to defeat John Isner 7-6 (5), 7-6 (4).
Trailing 5-4 in the first set, Isner fought off three set points before tying the set at 5-5. Nava later took a 4-2 lead in the first tiebreaker but needed three set points to win 7-5.
After the second-set tiebreaker was tied at 3-3, Nava broke serve to jump ahead at 5-3, and after Isner held serve at 5-4, Nava served out the set, winning on the first match point.
Elsewhere in the first round, wild card Taro Daniel of Japan advanced when France's Arthur Rinderknech retired while down 4-1 in the first set, and Frenchman Gael Monfils retired against countryman Ugo Humbert with their match tied 3-3 in the first set.
Other winners were Facundo Bagnis and Guido Pella of Argentina, Serbian Laslo Djere, Marton Fucsovics of Hungary, Marc-Andrea Huesler of Switzerland, Ilya Ivashka of Belarus, Brandon Nakashima and J.J. Wolf of the U.S., Australia's Alexei Popyrin, Emil Ruusuvuori of Finland and China's Yibing Wu.
--Field Level Media