He then joined French club Lyon, and in 2022 signed for English side West Ham United, winning the UEFA Europa Conference League in his debut season.

Alongside other standout players Léo Duarte, Felipe Vizeu, and Ronaldo, Lucas was promoted to the club's professional team right after the competition.

[6] Paquetá scored his first professional goal on 19 February 2017 in a 4–0 victory against Madureira at the Estádio Raulino de Oliveira in Volta Redonda.

On 10 October 2018, news agencies across Brazil and Italy reported that a €35M deal had been made between AC Milan and Flamengo for the transfer of player, beating stiff competition from French club Paris Saint-Germain.

[11] Paquetá made his club debut on 12 January 2019, playing 85 minutes before being replaced by Fabio Borini as Milan beat Sampdoria 2–0 in extra time in the Coppa Italia.

[12][13] Four days later, Paquetá played in the 2018 Supercoppa Italiana, held at the King Abdullah Sports City in Jeddah, Saudi Arabia,[14] where Juventus beat Milan 1–0.

Paquetá, 25 years old, competed with the defender of PSG Marquinhos, the Ivorian midfielder of Lens Seko Fofana and the Canadian leader of Lille Jonathan David.

[22] On 7 June 2023, Paquetá assisted Jarrod Bowen's 90th minute winner in the 2023 UEFA Europa Conference League final in a 2–1 win against Fiorentina in Prague.

Coach Rogério Micale called some younger players born in 1997 and 1998, including Lucas, to participate in group training in hopes of them eventually competing in the 2020 Summer Olympics in Tokyo.

[27] On 17 August 2018, Paquetá was called for the first time for the Brazil national team by manager Tite to play in friendly matches against United States and El Salvador in September.

[31] In the 2021 Copa América quarter-final clash against Chile on 2 July 2021, he came on as a substitute at half-time and scored in the 47th minute to give Brazil a 1–0 victory.

He faced four breaches of FA Rule E5.1 for his conduct during Premier League fixtures against Leicester City on 12 November 2022, Aston Villa on 12 March 2023, Leeds United on 21 May 2023, and Bournemouth on 12 August 2023, where it was alleged that he intentionally sought to receive a card from the referee to influence the betting market for personal profit.