Cristiano Ronaldo returned to goalscoring form with his first hat-trick of the season and also missed a penalty as Real Madrid extended their lead at the top of La Liga with a 4-1 win at Alaves on Saturday.

Ronaldo's wayward form in recent weeks had come under the spotlight -- he was booed by Real fans after missing one chance recently -- but he turned the game around after Deyverson had put Alaves into a shock early lead.

Ronaldo levelled from the penalty spot before his deflected effort put Madrid ahead at the break.

The Portuguese saw another penalty saved 12 minutes from time, but wasn't to be denied when he slammed home Marcelo's cut-back after Alvaro Morata's cushioned lob had made the game safe.

Real now lead Sevilla by three points at the top of the table and Barcelona by five.

However, Barca can cut the gap back to two points with victory at home to Granada later on Saturday.

"We are always going to demand goals from Cristiano, but he was good in all aspects," said Madrid boss Zinedine Zidane.

"We knew how to suffer because the first half and the start of the second weren't comfortable or easy.

"But playing like this, if you know how to suffer and then add a bit of movement, we know what we can do."

Real's unbeaten run stretches to 26 matches, but their defensive struggles continued in Vitoria as Zidane's men got off to the worst possible start when Deyverson pounced on an error from goalkeeper Keylor Navas to slot Alaves into a seventh-minute lead.

The visitors needed two slices of fortune to turn the game around before half-time.

Firstly, Deyverson was adjudged to have handled a Bale free-kick inside his own area and Ronaldo slotted home the penalty.

Ronaldo's second came 16 minutes later when his low effort from outside the area deflected off Zouhair Feddal and flew into the far corner.

Alaves had a huge chance to level just two minutes after the restart when Victor Camarasa skipped past Raphael Varane, but shot straight at Navas.

Madrid barely threatened in the second half until the last 15 minutes when they finally put the game beyond Alaves' reach.

Ronaldo was hauled down inside the penalty area from a corner, but saw his second spot-kick saved by Fernando Pacheco.

Morata again made his presence felt off the bench as he raced onto Marcelo's through ball and lobbed the onrushing Pacheco for his fourth goal as a substitute this season.