METZ, France (Reuters) - Much-maligned Olivier Giroud struck twice to help attack-minded France sink Scotland 3-0 in a final warm-up game on Saturday before they launch Euro 2016 on home soil next week.

Les Bleus scored three goals in an opening period that saw a weak visiting team totally dominated in midfield by Blaise Matuidi, Paul Pogba and N'Golo Kante, the latter's display in the holding position adding steel to the defensive unit.

Five days after fans booed Giroud during a friendly win over Cameroon, the Arsenal forward went a long way to reassuring them that he should be the focal point for a France team that have now notched 13 goals in four games.

Giroud, who has also faced regular criticism at club level, opened the scoring in the eighth minute with a superb back-heel after a perfect cross from Bacary Sagna.

He doubled his account 27 minutes later by stabbing the ball home after a Dimitri Payet shot was parried by goalkeeper David Marshall.

It took Giroud's tally to 17 goals in 49 internationals and he has now hit seven in his last seven matches for France.

"We created a lot of chances and I tried to be efficient," said Giroud after being substituted to the acclaim of the crowd.

Laurent Koscielny scored his first international goal just before halftime when he headed in a Payet corner.

The second period remained one-sided and France were unable to add to their tally mainly due to Marshall who pulled off a string of fine saves.

As well as criticism of Giroud, France's Euro 2016 preparations have been overshadowed by a row about alleged racism in the squad and a spate of injuries in defense.

It forced coach Didier Deschamps to gamble on the untested partnership of Koscielny and Adil Rami in a back line that appeared vulnerable against Cameroon.

However, with Scotland unable to muster a shot on target, questions remained over the defense in spite of a first clean sheet in four games.

"There are still things to improve," said Deschamps. "I would have preferred one or two more games to prepare but we'll be ready."

France play Romania in the opening game of Euro 2016 in Paris on Friday. They will also meet Albania and Switzerland in Group A later in the competition.

(Writing by John Irish; Editing by Tony Jimenez)