He won his maiden title at the 2020 Internazionali di Tennis del Friuli Venezia Giulia in Cordenons, Italy defeating Carlos Alcaraz.

He had his second ATP main draw win when he beat John Millman in the first round of 2021 Dubai Tennis Championships in straight sets.

130 at the 2022 French Open, Zapata Miralles qualified to make his second consecutive Grand Slam main draw at this Major.

He was the first Spanish qualifier to reach the fourth round of a Grand Slam since recording started in 1983.

At the ATP 250 2023 Córdoba Open he broke the record for the longest match ever in the tournament history when he defeated compatriot Roberto Carballés Baena in three hours and 26 minutes in the first round.

The previous-longest match was in 2020, when Albert Ramos Viñolas outlasted Pablo Andújar in three hours and 20 minutes.

At the 2023 Mutua Madrid Open he reached the third round of a Masters for the first time defeating Mackenzie McDonald and upset 19th seed Dan Evans.

Seeded 32nd for the first time at a Grand Slam at the 2023 French Open, he lost in the first round to Diego Schwartzman in five sets.

He lost also in the first round at the 2023 Wimbledon Championships to Tomás Martín Etcheverry after being two sets to love up in a 4 and 1/2 hours match over two days after play was suspended due to darkness.

[13] As a result of a couple of first round losses in the beginning of the season, his singles ranking fell outside the top 100 after the 2024 Rio Open.