The 27-year-old endured a disappointing start to life in Poland and Ukraine, but three goals in Portugal's last two matches have seen him move to the top of the tournament's scoring charts as the Seleccao prepare for their semi-final clash against Spain.
"Cristiano Ronaldo is aiming for his top form and, from what we have seen so far, he is the player at Euro 2012 who has come closest," Valdano told El Espectador.
"Andres Iniesta is very effective and he entered the tournament in a very god physical condition."
Valdano then shared his view on the early elimination of Netherlands, who crashed out in the group stage after suffering defeats to Germany, Denmark and Portugal.
"Unlike France, Netherlands were really disappointing, playing at a very low level, both individually and collectively," he added.
"They gave the feeling that they were emotionally broken."
Questioned about the managerial change at Barcelona, Valdano conceded that he was not surprised to see Pep Guardiola step down as coach after a successful four-year reign.
"[Pep] Guardiola was exhausted and he had every reason to be it," the 56-year-old explained.
"He had become a reference in football, but also a reference in the fans' morale, to the point that he had more power than club president Sandro Rosell or Lionel Messi.
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Cristiano Ronaldo is close to hitting top form for Portugal, says Valdano"It is not easy to be permanently on the spotlight and become a living legend. His ideas will last, because Barca's playing style has become a culture.
"But the team will undoubtedly lose the emotion that Guardiola transmitted, because he was capable of infecting the team with his excitement for football."
Real Madrid usurped Barcelona's throne in La Liga this season, setting a new record in the competition as they amassed a staggering 100 points.
"They won the league with authority and lost a great chance in the Champions League," Valdano noted.
"Their squad is only comparable to that of Barca, with young players who are very gifted technically.
"They also have a large squad, which allows them to play in different ways. In the next few years, they will have many more days of glory, because they are ready for big demands."