The nine-time Rome winner came through 6-1, 6-3 against the No.25-ranked Lajovic, who had valiantly but vainly launched a fightback after trailing 4-0 in the second set to the Spaniard.

World No.2 Nadal next meets No.8 seed Diego Schwartzman, from Argentina, who dropped a set before recovering to see off Poland's Hubert Hurkacz 3-6, 6-2, 6-4.

Nadal, 34, won his first Rome title back in 2005, and is bidding for a third consecutive crown on clay in the Italian capital and 10th in total.

The 12-time French Open champion is returning to competition, having not played since winning in Acapulco in February, opting to skip the US hard court tour because of coronavirus concerns.