[citation needed] Emerson made his Série A debut on 5 November 2017, replacing injured John Kleber in a 2–0 loss at Bahia.

[citation needed] Promoted to the first team ahead of the 2018 season,[7] Emerson became a regular starter for Macaca, making 14 appearances in the 2018 Campeonato Paulista.

[10] Emerson made his debut for the club on 19 May 2018, shortly after turning 19, playing the full 90 minutes in a 1–0 win over rivals Cruzeiro.

[12] The deal consisted of a joint financial operation between Barcelona and fellow La Liga side Real Betis, in which each club paid half of the transfer fee and retained a percentage of Emerson's economic rights.

[19] On October 1, 2022, during the second half of Tottenham's Premier League away game against Arsenal, Royal received a straight red card for his tackle on Gabriel Martinelli.

[21] On August 13, 2023, Emerson Royal scored a drilled shot from outside the box to secure a 2–2 draw against Brentford on the opening game of the 2023–24 Premier League season.

Due to a large amount of injuries at the club, Emerson filled in as a starter at left-back and centre-back as well as his natural right-back position throughout the first half of the season, widely impressing with his displays.

[citation needed] Emerson made his senior international debut for Brazil on 19 November 2019, coming off the bench in a 3–0 victory over South Korea.