Juventus will take a slender 2-1 advantage into next week's semi-final second leg in Spain after an early effort from Madrid-born Alvaro Morata and a second-half penalty from Carlos Tevez sandwiched Ronaldo's close-range header.
The Italians looked determined to make the most of their first Champions League semi-final in 12 years as they took the game to the visitors and were denied an early penalty claim when Arturo Virdal went down in the box.
Morata, who left Real for Juventus last summer, refused to celebrate when he slotted the opener after eight minutes after Tevez cut into the right side of the box and sent in a low cross.
The impressive Tevez was close to making it two when he dragged a shot across the face of goal after being sent clear by Stefano Sturaro, while Ronaldo uncharacteristically wasted a similar opportunity at the other end.
But Ronaldo could hardly miss in the 27th minute when James Rodriguez lofted a perfect cross across the face of goal and the Portuguese superstar was left with the simplest of opportunities to once again make history.
Rodriguez should have put the visitors in front in the 41st minute when he met an Isco cross with a diving header in front of goal which struck the bar before Marcelo knocked the rebound over.
Juventus continued to press early in the second half and referee Martin Atkinson pointed to the spot when Tevez was brought down by Daniel Carvajal in the 56th minute, the Argentinian picking himself up to hit a firm effort past Iker Casillas.
The home side continued to press for a third goal with Morata's replacement Fernando Llorente playing a central role in two chances in the dying minutes.
The Spaniard beat Raphael Varane on the right but could not quite cut the ball back for Roberto Pereira in the box, then he failed to connect in front of goal from an Andrea Pirlo free-kick.
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