Real Madrid were left stunned at the Mestalla Stadium as a defiant and plucky Valencia side held on for a 2-1 victory against Zinedine Zidane's men.

The visitors found themselves trailing in the opening 10 minutes as goals from Simeone Zaza and Fabian Orellana handed Vora's side an unexpected lead.

Real fought back, clawing one back through Cristiano Ronaldo's late first-half header, but the league leaders were unable to find an equaliser and remain just one point ahead of rivals Barcelona.

Here's five things we learned from this evening's game:

Madrid's champions credentials questioned

After falling two goals behind in the opening 10 minutes, tonight's game quickly progressed into the biggest test yet of Madrid's champions credentials. The visitors had the opportunity to pull four points ahead of rivals Barcelona, against a side that has struggled this season, but failed to effectively respond to Valencia's early lead. Madrid threw everything at their opponents but, on this occasion, sheer grit and defiance was enough to see out victory for Voro's men. For all their class and talent. Madrid have taken a sizeable psychological blow tonight and offered their title rivals hope.

Zaza proves his class

Simone Zaza's opener in the fourth minute was a thing of beauty. Bringing the ball down under intense pressure, spinning on the spot and then picking out the top left corner with his back turned to goal served to remind all those watching what the Italian is capable of. After a goalless draught of 15 matches, Zaza has now scored in back-to-back games. He recently admitted his regret that he had not shown "in England what I'm capable of" but after tonight's performance, there's no reason he can't go on to make a name for himself in Spain.

Ronaldo heads home for Madrid (Getty)

Valencia's counter-attacking days needn't be a thing of the past

Under former manager Rafa Benitez, the Oranges were famed for their fast, slick counter-attacking style of football. Under pressure, Valencia were content to sit back, condense and then react with phenomenal pace. Although the home side have struggled for results and form this season, this evening's performance, especially in the opening 20 minutes, suggests that such a style of football need not be a thing of the past. Work and development is needed, of course, but it bodes well for the side as they bid to put further distance between themselves and the relegation zone.

Ronaldo falls down under pressure from Valencia's Mangala (Getty)

James fails to seize his big opportunity

The Colombian was handed a rare start under Zinedine Zidane but, when push came to shove, the 25-year-old struggled to deliver. James slipped under the radar for much of the game, failing to dictate the run of play as others around him put in the hard work. It's game like these, against lesser sides such as Valencia, where the Colombia international should be proving his worth to the side. More is needed from him.

Modric in possession for Madrid (Getty)

Ronaldo needs to share responsibility