Both players were outstanding for the Danes' victory over Holland in their Euros opener.
"Bendtner lived in a bubble when he came into this team," said Agger. "He was always 'here I am' and 'I can do it', but he has really evolved in a positive direction.
"Just look at the match on Saturday and see how much he ran for the team. Often he got nothing out of it himself, but he helped the team by putting pressure on so we could get the ball."