He was outstanding on the left-flank as he fired in a ideal cross to Coutinho at the back post who slid in to volley his effort into the back of the net via the ground.
The match was tied 0-0 after 34 minutes with Barcelona bringing a 1-0 aggregate advantage to the Mestalla as both pushed for a breakthrough.More news: Ligue 1: Confident PSG ready for Real Madrid - Emery
Back in February 2013, nearly five years ago, Coutinho scored his first goal for Liverpool on his full debut against Swansea City.
Barcelona finally managed to land their target as Coutinho arrived at Camp Nou for a club-record fee of £142m ($198m) in the January transfer window.
Following his mega-money move from Liverpool, Philippe Coutinho will have been hugely disappointed to have seen that he would start on the bench for the semi-final. It'll be a great game and a hard one (against Sevilla in the final).More news: North Korea confirms dismissal of top military general
The best chance of the first half fell the way of Valencia when Rodrigo saw his header come crashing off the underside of the bar with Jasper Cillessen in the away goal beaten all ends up.
The Blaugrana will naturally be favourites for this contest, too, but Sevilla have the capacity to overcome them over 90 minutes if they can get their approach and performance right on the day.
"We're really happy to reach the final". Suarez also set up the second goal, finding Rakitic for an easy goal from inside the area after a breakaway in the 82nd minute. Speaking after the game, Valverde said: "It normally takes a little longer to make the changes. Gomes was helping us with his strength to be together up and back, but I saw that with the domain we had we needed a player (Coutinho) who could bargain at the last moment".More news: Eleven Turkish troops die, chopper down in deadliest day of Kurdish offensive
It will be Barca's fifth Copa del Rey final in as many years and the 40th in the club's history.
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