Luis Suarez can get Barcelona off to a flyer
Valencia trail after first leg
Copa del Rey semi-final second leg
The Catalans lead 1-0 after last Thursday's first leg at Camp Nou and could have established a more convincing advantage after dominating the shot count 17 to one.
It is a narrow lead but history is on the side of Barca, who have recorded six 1-0 home wins in Copa del Rey first-leg ties and gone on to qualify on each occasion.
Barcelona extended their La Liga unbeaten sequence to 29 matches on Sunday after Gerard Pique's 82nd-minute goal rescued a 1-1 draw away to city rivals Espanyol.
They hold a nine-point lead over Atletico Madrid in the title race and can afford to focus fully on the Valencia contest without worrying too much about Sunday's league match at home to Getafe.
The league may be more of a distraction to Valencia, who are coming under pressure in their quest for a top-four finish.
Los Che have lost their last three league games and are only three points ahead of fifth-placed Villarreal.
They have scored just three goals in the last five matches, all by forward Santi Mina, and may have to take a few risks to forge a way back into the tie.
However, by playing on the front foot they may leave spaces for Barca's star attackers Lionel Messi and Luis Suarez to punish them on the counter-attack.
Suarez has netted 14 goals in his last 14 games, including the first-leg winner against Valencia, and looks a value bet in the first-scorer betting.
L Suarez first scorer
1pt 10-3 bet365
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