De Minaur, 24 years old and number 22 in the world, defeated Pacheco, 17 years old and 1,244 in the ranking, in one hour and 16 minutes.
“Rodrigo is going to be a very good player, he learns a lot and quite quickly, and I am very happy with my performance today,” said De Minaur at the end of the match.
Italian Matteo Berrettini had no complications in eliminating Slovak Alex Molcan in 45 minutes, beating him 6-0 in the first set before retiring due to injury in the second when he was already trailing 1-0.
This Tuesday, the Spanish Carlos Alcaraz, first seed, and the British Cameron Norrie, fifth seed, were dropped from the tournament due to physical problems.
The lucky loser who relieved Norrie was the Swede Elias Ymer, who eliminated the Frenchman Adrian Mannarino in three sets with partials of 5-7, 6-3 and 6-4 in two hours and 33 minutes.
The Italian Luciano Darderi was the ‘lucky loser’ who took the place of Carlos Alcaraz and was eliminated by the American McDonald MacKenzie in two sets by a score of 4-6 and 2-6 in one hour and 15 minutes.
The Acapulco Open is an ATP 500 category tournament that distributes a bag of 1.8 million dollars in prizes and is played on the hard surface courts of the GNP Arena.
Tuesday’s first round matches:
Matteo Berrettini (ITA) defeated Alex Molcan (SVK) 6-0, 1-0 retirement due to injury
Nuno Borges (POR) to Nick Chappel (USA) 6-3, 7-6 (7/3)
Elias Ymer (SWE) def. Adrian Mannarino (FRA) 5-7, 6-3, 6-4
Brandon Nakashima (USA) def. Daniel Altmaier (GER) 6-3, 3-6, 6-1
Jacopo Berrettini (ITA) def. Oscar Otte (GER) 3-6, 7-6 (7/3), 2-1 retired due to injury
McDonald MacKenzie (USA) def. Luciano Darderi (ITA) 6-4, 6-2
Alex de Minaur (AUS) def. Rodrigo Pacheco (MEX) 6-1, 6-2