Two-time Miami Open champion Andy Murray has been eliminated in the first round of this year's event after a shock 6-4 7-5 loss to world number 76 Dusan Lajovic on Wednesday.

Murray, ranked 53rd in the world, could not find his usual return with Lajovic winning 72 per cent of second-serve points, prevailing in one hour and 38 minutes.

The Serbian claimed only his fourth win out of 16 matches on hard courts since the start of last year, holding his nerve after failing to serve out the match at 5-4 in the second set, converting his third match point in the 12th game.

Lajovic hit 21-14 winners, with Murray committing more unforced errors (15-13). The Serbian converted all three break points he generated.

Former world number six Gael Monfils was forced to retire due to a right wrist injury in his clash with French compatriot Ugo Humbert at 3-3.

Monfils, 36, was playing at only his third event since returning to the ATP Tour following seven months out due to injury.

Argentina's Facundo Bagnis defeated Brazilian qualifier Felipe Meligeni Alves 6-3 1-6 6-4, with his reward a second-round clash with last week's Indian Wells Open winner and top seed Carlos Alcaraz.

World number 50 J.J. Wolf beat world number 48 Alexander Bublik 7-5 6-3 in 79 minutes, earning a second-round clash with sixth seed Andrey Rublev.

World number 74 Martin Fucsovics sent down nine aces as he beat Argentina's Pedro Cachin 6-4 7-6 (7-2) in 107 minutes. Fucsovics will next face seventh seed Holger Rune.

Ilya Ivashka beat Daniel Altmaier 6-2 6-1 to book a second-round clash with third seed Casper Ruud, while Fabio Fognini bowed out, losing 6-4 5-7 6-4 to Jan-Lennard Struff. USA's Brandon Nakashima powered to a 7-6 (7-3) 6-3 victory over Germany's Oscar Otte.