The England boss started Phil Jones in midfield for the 1-0 win over Spain and introduced Danny Welbeck, Jack Rodwell and Kyle Walker as second-half substitutes at Wembley.
And after the game, Capello hinted the national side’s younger talents could all play vital roles in Poland and Ukraine.
“The most important thing I saw was the performance of Rodwell and Jones and Welbeck, really good young players and also Walker,” he said.
“I think these players will be very important for the Euros because I saw they played without fear and with personality and physically and technically I can see they are good to play with the seniors.”
Meanwhile, Capello was impressed by performance of England centre-halves Phil Jagielka and Joleon Lescott, whose admirable displays at Wembley helped his side keep a clean sheet against the world champions.
“The two centre-backs played a fantastic game, really good,” he continued.
“Every time Spain tried passes through they were in good positions. They played with big confidence. It is impossible to play against Spain without confidence.
“John Terry and Cahill will play against Sweden. Walker will play right-back and [Daniel] Sturridge and [Bobby] Zamora [will also play].
“I needed to know the value of the players when they play here at Wembley. This is big test for good players to play here.”
Scott Parker was named man of the match following an impressive performance in front of England’s back four – and Capello hailed the midfielder’s growing importance to the national side.
“Scott Parker had an incredible performance,” he added. “He is improving every game and he is a really important player for the back four when they receive the ball.”
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