Josip Ilicic said Atalanta are "no longer a surprise" after putting one foot in the Champions League quarter-finals with a crushing win over Valencia.

Champions League debutants Atalanta continued their fairytale run by routing Valencia 4-1 in the opening leg of the last-16 tie at San Siro in Milan on Wednesday.

Atalanta, who lost their opening three group matches this season, put the Spanish visitors to the sword courtesy of Hans Hateboer's brace and goals from Ilicic and Remo Freuler.

"We prepared this game the same way we always do and had a great first half, allowing them practically nothing. It's a pity we conceded that away goal, but Valencia are a strong team and we forced them to play badly with our football," Ilicic, who scored a stunning goal to make it 2-0 approaching half-time, told Sky Sport Italia.

"We knew their centre-backs didn't push up much, so that's why the coach chose me with Papu Gomez up front. We were very dangerous, especially in the first half, but we can do better.

"Atalanta are no longer a surprise, we've proved so many times that we don't give in. We're doing some really important things here."

Atalanta head coach Gian Piero Gasperini added: "We are on the one hand very satisfied, as we'd have happily accepted a scoreline like that.

"Yet we end up feeling regret over conceding that away goal, as we really shouldn't have made that mistake when 4-0 up and it wasn't the only situation like that.

"We need to be more precise when we go to the Mestalla. If we want to get into the Champions League quarter-finals, we have to play like this at the Mestalla too, prove we deserve to be there with a show of strength and win there too.

"We are a team who create many chances, it could perhaps have had more goals for us and them tonight. We created our goals, they sort of received gifts from us on theirs. We got a bit euphoric and lost sight of our concentration at times.

"We'll analyse now what we got wrong and learn from these errors, as we want to prove in the second leg that we deserve to be there.

"We've got to score there too. We will do some defending, but I don't want us to go to Spain and just sit on a three-goal lead, suffering the entire time."

Denis Cheryshev's 66th-minute consolation gave Valencia some hope ahead of the return leg on home soil and Valencia boss Albert Celades said: "This result doesn't really reflect what we saw on the pitch.

"I think the difference was that Atalanta scored practically every chance they had, which is not an easy thing to do. We didn't score when we had the opportunities. Of course, we made mistakes. When you play at this level against a side like Atalanta, you cannot allow them all that space. We did create our opportunities, though, and that is important for the second leg.

"I think we've got a chance of turning it around. The result is pretty clear tonight, but we'll see what happens at the Mestalla. We play well in our own stadium. We concede too many, especially away from home, there's no denying that. It won't be easy to overturn this situation, but we will try."