Erik ten Hag was thrilled with Ajax's clinical display against Valencia, but the head coach claimed his side must improve defensively despite a second successive Champions League clean sheet.

Ajax stormed to a 3-0 victory on Wednesday at the Mestalla, making it two wins from two in Group H for last season's semi-finalists.

Things would have been different had Dani Parejo not wasted a golden chance for Valencia to equalise when he skied a penalty, however – with Quincy Promes soon adding to Hakim Ziyech's early opener to double Ajax's advantage.

Some weak defending allowed Valencia into the contest again early in the second half, but the hosts found Andre Onana in superb form.

Ten Hag acknowledged Ajax, who could still be adjusting to life without Matthijs de Ligt, must improve at the back, though he emphasised the outstanding quality of his attackers.

"There are things that could be better, such as defensively. We had problems there, but they [Valencia] also had problems with us," Ten Hag told reporters.

"We played a fantastic match and deserved to win. I still believe we have some things to improve, but we can play such fantastic football.

"At times on the sideline I can really enjoy us playing football. Not many teams can do this at [the] Mestalla."

Ajax demonstrated their slick play in the build-up to Donny van de Beek's second-half strike – Dusan Tadic slotting a deft reverse pass into the midfielder, who duly wrapped up the win.

Yet Ziyech was the star. His stunning effort opened the scoring eight minutes in, while he also saw a second long-range shot clatter off the crossbar just before half-time.

"Ziyech could excel and we could play him freely. I was hoping for that in advance, so it worked out well," said Ten Hag, who also hailed goalkeeper Onana's performance.

"Multiple players can make a difference. [Onana] is one of them. We also have creativity in attack and can play great football. We have taken a big step but we are not there yet."

As well as Parejo's woeful miss from the spot, Valencia twice hit the post through Rodrigo either side of half-time and coach Albert Celades was left to rue a glut of wasted opportunities. 

"It's a tough loss. It's a heavy defeat, maybe not deserved, but that's what happened," Celades said.

"We had chances in the first half but didn't take them, but we played well. They were more clinical than us.

"It's difficult for all of us but looking deeper than the result we are doing well. The first half was very good but they punished our poor finishing."