Angel di Maria handed Madrid the lead after just 11 minutes, with that strike the difference between the two sides at the interval.
Read how it all unfolded in Sports Mole's minute-by-minute live commentary of the action below.
¡Cabalgamos juntos, morimos juntos! ¡¡HALA MADRID!! pic.twitter.com/kbHjMxQe9V— Álvaro Arbeloa (@aarbeloa17) April 16, 2014
2 - Real Madrid have only won two of their last seven Copa del Rey finals, though these were both played in Valencia. Mediterranean.— OptaJose (@OptaJose) April 16, 2014
3 - Carlo Ancelotti has only lost three of his 11 finals as a manager, with two of those defeats coming in a penalty shootout. Expert.— OptaJose (@OptaJose) April 16, 2014
4 - Barcelona have won four of their last five Spanish Cup finals, losing only to Jose Mourinho's Real Madrid in 2011 (0-1). Bite.— OptaJose (@OptaJose) April 16, 2014
BARCA: Pinto; Alves, Mascherano, Bartra, Alba; Busquets, Xavi, Iniesta; Neymar, Fabregas, Messi
MADRID: Casillas; Carvajal, Pepe, Ramos, Coentrao; Alonso, Modric, Isco; Di Maria, Benzema, Bale
2 - Real Madrid have won two of their three previous Spanish Cup finals against Barca in Valencia (2-1 in 1936 and 1-0 in 2011). Rivalry.— OptaJose (@OptaJose) April 16, 2014
Inside Mestalla just now... ground still to fill up... 20,000 fans from each side expected in 55,000 sell-out. pic.twitter.com/EBUcrLvOxG— Dermot Corrigan (@dermotmcorrigan) April 16, 2014
1 - Marc Bartra will make his Clasico debut tonight, Isco is playing in only his second. Nerve.— OptaJose (@OptaJose) April 16, 2014
The groundsmen are out giving the turf a final buffing.— AS English (@English_AS) April 16, 2014
19 degrees in the Mestalla, slight breeze swirling round.— AS English (@English_AS) April 16, 2014
3 - Ángel Di María has been involved in three of Real Madrid's last four goals against Barcelona (one goal and two assists). Electro.— OptaJose (@OptaJose) April 16, 2014
Messi looking fed up not for the first time. FCB playing too many crosses, not using his strengths. When that happens, his mind switches off— Guillem Balague (@GuillemBalague) April 16, 2014
1 - Marc Bartra is the first Barcelona player to score a header in El Clasico since Puyol in 2012, also in the Copa del Rey. Replacement.— OptaJose (@OptaJose) April 16, 2014