SAINT-DENIS, France — France defender Samuel Umtiti looks set to spend Sunday night trying to stop Cristiano Ronaldo from scoring for Portugal in the European Championship final.

Two months ago it seemed highly unlikely Umtiti would even be at the tournament.

But the 22-year-old center half is now tipped to start after an impressive performance in the 2-0 win against Germany in the semifinals.

“He has the mental strength and character to play at the highest level,” said France Coach Didier Deschamps.

He didn’t previously seem so sure.

When Deschamps named his 23-man squad May 12 – before UEFA’s May 31 deadline – Umtiti was only among the eight reserves.

Two weeks later, Real Madrid center half Raphael Varane pulled out with a thigh injury.

It seemed logical that Umtiti would be called up. But instead Deschamps chose Adil Rami, even though Rami wasn’t on the reserve list.

But as France’s defensive woes worsened, with Jeremy Mathieu being ruled out with a calf injury, Umtiti finally got called up May 28.

Just in time.

Ironically, Umtiti took Rami’s place in the lineup, making his international debut against Iceland in the quarterfinals. Having previously overlooked him, Deschamps is now a big fan.

“He knows that I believe in him despite his young age,” Deschamps said Saturday. “Some people aren’t even mature at 30 while some are at (22), which is his case.”

It’s been a hectic few weeks for Umtiti, who is joining Barcelona from Lyon. His upsurge in form is surprising given how poorly he played during last season’s Champions League, where Lyon finished bottom of its group. But Umtiti finished the season strong as Lyon hit form to finish second in the French league behind Paris Saint-Germain.

Born in the Cameroonian capital of Yaounde, he rose through Lyon’s widely admired youth academy before making his debut in the 2011-12 season.

Against Germany, Umtiti made two crucial interventions.

The first came in the 32nd minute when he stole the ball from forward Thomas Mueller just as Mueller was about to shoot. Early in the second half, with Germany down 1-0 and pressuring strongly, he made a key interception to thwart a dangerous break by winger Julian Draxler.

Umtiti also passed well from the back and cleared danger with commanding headers from crosses.

”Technically he’s ready, mentally he’s ready,” veteran France right back Bacary Sagna said. “It’s the start of something special for him.”