Milan (AFP) – Italy coach Gian Piero Ventura has warned that failure to get it right against Spain in a crucial World Cup qualifier next September could prove costly.

Goals from Lorenzo Insigne, Andrea Belotti, Eder, Federico Bernardeschi and Manolo Gabbiadini in a 5-0 rout of Liechtenstein sent unbeaten Italy to their fifth win in Group G in Udine on Sunday.

But a lack of clinical finishing meant the Azzurri failed to pile on even more goals that could have seen them leapfrog Spain to take command of the group.

Spain, who secured a precious 2-1 win over Macedonia on Sunday, remain top with a superior difference of four goals.

Although both teams will have three qualifiers to play following their Madrid clash on September 2, it is being billed as decisive for both as they look to secure top spot and the sole automatic qualifying place. The runners-up up will be forced to a qualifying play-off.

While buoyed by a performance that saw Italy run Liechtenstein ragged for almost the entire 90 minutes, Ventura said: “Our first half will serve as a lesson for our next game, in Madrid.

“If we head to Spain trying to do things too quickly, we’ll end up messing it up.

“In the second half we did things as we should have, we played with a lot more lucidity and the chances came, and eventually so did the goals.

“In the second half alone we created seven or eight clear chances. That’s what I mean when I talk of patience: let’s try to remember that in Madrid.”

Amid a sterling performance in the number 10 jersey, Napoli forward Lorenzo Insigne broke the deadlock with a superb curling strike on 35 minutes.

But it took Ventura’s men until the second half to make an impact, Insigne threading through for Torino striker Andrea Belotti to hit Italy’s second on 52 minutes.

A series of chances went begging before Italy scored three goals thanks to second-half substitutes Eder (Inter Milan), Bernardeschi (Fiorentina) and Southampton’s Gabbiadini.

It was Bernardeschi’s maiden Italy goal, having made his debut in Udine when Italy hosted Spain in a friendly last year.

But the stand-out performer for Italy was Insigne, whose movement, vision, ball control and passing made the difference.

“We gave it everything, but the most important thing was to win,” said Insigne, who echoed Ventura’s thoughts for Spain ahead of their meeting in 10 weeks’ time. 

“We know it will be a difficult game, we’re playing in Spain, but with the correct approach and playing like as team as we did tonight (Sunday), I’m sure we’ll produce a solid performance and hope fully the right result.

“We’re all committed to the national cause.”