Costa double leads eight-goal start for Lopetegui's Spain

Costa scored his first Spain goal since 2014 after just 10 minutes, but despite complete domination of the game the hosts had to settle for just a one-goal lead at half-time.

The floodgates opened with three goals in five minutes after the break as Sergi Roberto and Vitolo tapped home their first international goals either side of David Silva's third.

Costa headed his second into the top corner before being replaced by Alvaro Morata, who hit a quickfire double of his own in the last 10 minutes.

Silva added an eighth in stoppage time to become Spain's fifth highest goalscorer of all-time behind Hierro, Raul, Fernando Torres and David Villa with his 28th international strike.

"We reaped our rewards in the second-half for what we did right in the first-half," said Lopetegui.

"I am happy. They are the first three points and it was important to start well."

A comprehensive win puts Spain top of Group G in qualifying for the 2018 World Cup ahead of Euro 2016 conquerors Italy on goal difference after the Azzurri won 3-1 in Israel.

Spain and Italy meet in their next qualifier in Turin on October 6.

"They are another three important points, (but) it is not decisive. It is just one match of 10 (in qualifying.)

"We have the hunger and desire for that match, but there is still a month to go."

Lopetegui made just two changes to the side that won impressively 2-0 in a friendly away to Belgium on Thursday with Costa and Sergi Roberto replacing Real Madrid pair Morata and Dani Carvajal.

Costa ended his long wait for just a second international goal when he met Koke's excellent in-swinging free-kick to give Spain the perfect start.

"I am participating much more in the play and when you participate more the goals will come," said Costa.

The Chelsea striker had complained after the match against Belgium that he is too easily criticised for his Spain performances as a naturalised Brazilian.

However, he reeled back from those comments, describing the criticism he has received for his under-par displays at international level as "normal."

"My teammates have been with me from the first day, the fans the same.

"The criticism is normal. When you play for the national team people always demand more."

Chances started to flow at the start of the second period and Sergi Roberto finally netted the second on his competitive international debut when he slotted the ball between Peter Jehle's legs from Nolito's excellent pass.

Vitolo's low cross was then blasted home from point-blank range by Silva.

The Manchester City playmaker resorted to his normal role a minute later with an enticing pass for Vitolo to roll home the fourth.

Costa doubled his tally for the evening at the second attempt after his first effort was repelled by Jehle.

However, the Lichtenstein captain was at fault for both Morata's goals as he merely parried powerful strikes into his own net.

Silva had a goal wrongly ruled out for offside, but still had time to leapfrog Fernando Morientes as the fifth most prolific Spaniard of all-time with a finely struck low effort from the edge of the box.