PARIS (AP)—Although France is improving and unbeaten in 16 matches, coach Laurent Blanc still has not decided what his first-choice team is and will continue to experiment against old rival Belgium in Tuesday’s friendly match.

Real Madrid striker Karim Benzema, AC Milan defender Philippe Mexes and Lyon goalkeeper Hugo Lloris have emerged as France’s key players over the past year, but other places are up for grabs ahead of next year’s European Championship.

Blanc says he has “players vying for each position” but is also unsure what system suits France best.

The flat 4-4-2 he started with in Friday’s 1-0 win against the United States was unconvincing, and France played with far greater fluidity when playmaker Marvin Martin and versatile striker Loic Remy came on.