|Hakim Ziyech fired home a magnificent opening goal. (AFP/JAVIER SORIANO) |
Ziyech's stunning strike gave Ajax an eighth-minute lead at Mestalla, before Daniel Parejo missed a penalty for the hosts and Quincy Promes made it two.
An excellent team goal, finished off by Donny van de Beek, capped another eye-catching display by Ajax as they continued to make light of losing Frenkie de Jong and Matthijs de Ligt to Barcelona and Juventus in the close season respectively.
"In the first half, Valencia were much better, in my eyes. We didn't defend well," the 22-year-old Van de Beek told uefa.com.
"The second half was much better - we made nice goals and winning 3-0 away is really nice. We made the chances and finished them well. In the end, we could have had one or two goals more."
Erik ten Hag's men now lead the group by three points from Valencia and Chelsea after the Londoners edged out Lille 2-1 in France in Wednesday's other game.
Ajax beat Lille 3-0 in Amsterdam a fortnight ago and have now stretched their unbeaten away run in the Champions League, including qualifiers, to 13 matches.
"I still believe we have some things to improve, but we can play such fantastic football," said Ajax coach Ten Hag.
"At times on the sideline I can really enjoy us playing football. Not many teams can do this at Mestalla."
It was Valencia heaviest European home loss since a 3-0 reverse against Swansea City in the 2013-14 Europa League group stage, and their worst in the Champions League for 15 years, dating back to a 5-1 thrashing by Inter Milan.
"It's a tough loss. It's a heavy defeat - maybe not deserved but that's what happened," said Valencia coach Albert Celades.
"We had chances in the first half but didn't take them, but we played well. They were more clinical than us in front of goal."
PAREJO BLAZES OVER
The Dutch champions, who won at Real Madrid, Juventus and Tottenham in last season's competition, wasted little time in forging ahead as Ziyech collected the ball on the right wing, before cutting inside and unleashing a venomous hit that flew into the top corner from 25 yards out.
Celades, who took over as Valencia boss following the controversial sacking of Marcelino, saw his team blow a chance to level as Parejo blazed a horrible penalty over.
The Dutch side made the Valencia captain pay just nine minutes later, as Van de Beek teed up Promes to score after good work by Dusan Tadic.
Moroccan international Ziyech almost repeated his earlier wonder-strike as he jinked inside again and rattled the crossbar, before Rodrigo poked the ball against the foot of the post from close range at the other end.
Valencia kept plugging away in search of a way back into the match, going close through Ferran Torres, but saw their hopes of a comeback ended by another wonderful Ajax goal midway through the second half.
Quick passing opened up the home defence and Tadic slipped the ball through for midfielder Van de Beek, who had plenty of time to settle himself and slot it into the net.
UEFA Champions League results:
Genk (BEL) 0 Napoli (ITA) 0
Liverpool (ENG) 4 Red Bull Salzburg (AUT) 3
Slavia Prague (CZE) 0 Borussia Dortmund (GER) 2
Barcelona (ESP) 2 Inter Milan (ITA) 1
RB Leipzig (GER) 0 Lyon (FRA) 2
Zenit Saint Petersburg (RUS) 3 Benfica (POR) 1
Lille (FRA) 1 Chelsea (ENG) 2
Valencia (ESP) 0 Ajax (NED) 3