Britain's Andy Murray beat Argentine Federico Delbonis in the first round of the Miami Open to set up a meeting with top seed Daniil Medvedev.
The Scot, ranked 85th in the world, won 7-6 (7-4) 6-1 against Delbonis.
Murray, 34, a two-time winner, will play Russian Medvedev, who lost the world number one ranking on Monday.
Medvedev spent three weeks at number one and must reach the semi-finals in Miami to again replace Serb Novak Djokovic at the top of the men's game.
Murray won four consecutive points to edge an even opening set in a tie-break at Hard Rock Stadium - but he made lighter work of the second set, breaking the Delbonis serve for 1-0 and 4-1 leads before another sealed the victory.