Born in Almussafes, Valencian Community, Ruiz joined FC Barcelona's youth setup in 2012, from Valencia CF. On 21 November2016, he renewed his contract with the club. On 9 April 2017, while still a junior, Ruiz made his senior debut with the reserves, coming on as a late substitute for Jesús Alfaro in a 2–0 Segunda División B away win against CF Badalona; he also became the first player born in the 2000s to make an appearance for the club's senior ranks. After Barcelona B's promotion, Ruiz made his professional team debut on 28 August2017, replacing David Concha in an 0–3 home loss against CD Tenerife for the Segunda División championship. Four days later he scored his first professional goal in a 2–2 draw against Granada CF. Ruiz had his first-team debut in the Supercopa de Catalunya on 7 March2018, scoring the winning penalty in a shootout against RCD Espanyol. His La Liga debut came on 12 May 2019 in a 2–0 win against Getafe CF, as a substitute for Philippe Coutinho for the final 21 minutes at the Camp Nou. On 31 January 2020, Ruiz joined Portugal's S.C. Braga on loan for the rest of the season, with a mandatory purchase for €8 million and a buy-back clause. He made his debut on 20 February in the last 32 first leg of the UEFA Europa League away to Rangers, starting the game and scoring in a 3–2 loss. Totalling eight appearances over the season, he scored his first Primeira Liga goal on 4 July soon after entering in a 4–0 home win over C.D. Aves.
International career
Ruiz made his debut for the Spain under-17 team on 25 October 2015, starting and scoring the first in a 2–0 2016 UEFA European Under-17 Championship qualification win against Andorra. He was also named in the list for the finals in Azerbaijan, despite being one year younger than his teammates. Ruiz finished the competition with four goals, being awarded the Silver Boot; he was also included in the tournament's best eleven. During the 2017 edition in Croatia, he captained the side as Spain achieved their ninth title. On 22 September 2017, Ruiz was included in Santiago Denia's squad ahead of the 2017 FIFA U-17 World Cup, and scored two braces in the tournament, scoring two goals in a 4–0 win against Niger on 10 October, and two more in a 3–1 semi-finals win against Mali on 25 October.
