Promoted to the latter's first team for the 2016–17 season in the Segunda Liga, Costa's first match in the competition took place on 6 August 2016, when he played 62 minutes in a 1–0 away loss against Gil Vicente FC.[2] He went on to score 14 goals, helping his team to the ninth position and being voted Best Newcomer of the Year in that level.[3]
Portimonense
Costa was loaned by Primeira Liga side Portimonense S.C. to Famalicão in August 2017.[4] In October/November of that year, he netted three consecutive braces in the league in as many wins.[5][6][7]
In January 2018, Costa had everything arranged to join FC Porto B. However, after it was discovered that he had been registered by Varzim five days prior to signing with Portimonense – thus representing three clubs in the same season – the move was declared void.[8] He made his debut in the Portuguese top flight on 31 March, coming on as a 75th-minute substitute in a 4–3 home victory over Moreirense FC.[9]
Porto and Deportivo
In July 2018, Costa was finally made a part of Porto B's setup.[10] A year later, he moved abroad for the first time in his career after agreeing to a one-year loan deal with AD Alcorcón in the Spanish Segunda División.[11] He continued in the country in September 2020, signing a two-year contract with Deportivo de La Coruña who had just been relegated from the same league; Porto remained entitled to 50% of any future transfer.[12]
Costa moved to second-tier S.C. Farense on 1 September 2022.[19] Even though mainly a substitute, he scored nine times in his debut campaign, helping to promotion as runners-up.[20][21]
^Alves, Armando; Monteiro, André (7 June 2018). "Rui Costa já é reforço do FC Porto" [Rui Costa is already a FC Porto addition]. Record (in Portuguese). Retrieved 31 July 2019.
^"Oficial: Rui Costa" [Official: Rui Costa] (in Portuguese). C.D. Santa Clara. 1 February 2021. Retrieved 3 February 2021.
^Marques, David (5 March 2021). "Sporting-Santa Clara, 2–1 (crónica)" [Sporting-Santa Clara, 2–1 (report)] (in Portuguese). Mais Futebol. Retrieved 27 January 2022.