Fabio Capello faces a selection dilemma in defence ahead of England's Euro 2012 qualifier against Bulgaria, with Manchester United pair Chris Smalling and Phil Jones in contention to start ahead of more experienced duo Gary Cahill and Phil Jagielka.
Injuries to Glen Johnson, Rio Ferdinand and Michael Dawson could force the Italian boss to hand debuts to the youngsters, who have stared in defence for United this season.
Both players have just a handful of Barclays Premier League starts between them, with Smalling's experience at full-back limited to just four games this season.
Capello said: "He surprised me when he played at Wembley in the Community Shield against Manchester City.
"He played well. In fact, the four games that he's played at right-back, he's played really well. I always saw him play in central defence before. He is playing with confidence. He has improved and improved."
The pair have experience of having played with each other away from their club, having figured impressively at the heart of the England Under 21s defence during this summer's European Championships.
However, with England requiring a win to maintain top spot in Group G alongside Montenegro, Capello may turn to experience in the form of Cahill and Jagielka, or even Micah Richards, who has found regular appearances during his Italian's tenure difficult to come by.
"Some are ready, some are probably a risk because they didn't play at this level in such important games with the national team," Capello added.
"When you play important games for your club, you know the players who play with you, their movement, where you receive the ball.
"Here it's different. You play with the other team-mates, but sometimes you are alone."