Diego Costa enjoyed a typically eventful return to action for Atletico Madrid on Wednesday, scoring within six minutes of coming off the bench in his side's 4-0 Copa del Rey win at Lleida Esportiu but appearing to injure his knee in the process.
Costa turned Juanfran's low cross into the net in the 69th minute for Atletico's third goal in the first leg of the last 16 tie against third division Lleida but immediately limped to the sidelines. He did return to the pitch, however, and completed the game.
Diego Godin had headed Atletico in front in the 33rd minute following a free kick and Fernando Torres slid in to double the lead, completing a sweeping counter-attack although he was fortunate not to be ruled offside.
Antoine Griezmann completed the rout with a goal from a free kick in stoppage time, moments after the home side had defender Marc Trilles sent off for a second yellow card.
The win put Atletico on the verge of the quarter-finals, with the second leg at their Wanda Metropolitano stadium on January 9.
Spain international Vitolo, a 40 million-euro signing from Sevilla who spent the first half of the season on loan at Las Palmas, also made his debut for Atletico by coming on in the second half.
Costa completed a £57million move back to Atletico from Chelsea in September, having left the club in 2014 after firing them to the Liga title. The move was delayed by the club's ban on registering new players which expired on January 1.
Costa gave his side an extra edge, charging into challenges and provoking opponents as well as starting and finishing the move for the third goal, his first strike for Atletico since scoring against Chelsea in April 2014.
Last year's runners up Deportivo Alaves won 3-1 at tiny island side SD Formentera, while Sevilla beat Cadiz 2-0 with first-half goals from Nolito and Jesus Navas.
In the other match, Rodrigo grabbed a late equaliser for Valencia against Las Palmas after Jonathan Calleri had put the hosts in front.