MADRID - A Cristiano Ronaldo header set Real Madrid on their way to a 4-0 win at home to 10-man Racing Santander on Saturday that stretched their advantage over second-placed Barcelona at the top of La Liga to 13 points.

Ronaldo's sixth-minute goal from a clever Kaká assist was his 28th of the season in the league

Santander, who are 18th in the standings, were reduced to 10 men six minutes before the break when the referee ruled defender Domingo Cisma had handled the ball and showed him a second yellow card.

Real doubled their lead in added time when a dinked Karim Benzema effort was deflected over the line by Santander defender Bernardo.

Substitute Angel Di Maria, back after injury, netted the third goal and the best of the night in the 73rd minute when he powered a left-foot strike past goalkeeper Tono from just outside the area.

Benzema's deflected effort made it 4-0 a minute from time to seal an 18th win for Jose Mourinho's side in 19 league matches since the end of September and lift them to 61 points from 23 games.

"The best thing is that we have three more points and one less game to play," Mourinho told a news conference. "We won without sparkle, but without much effort," the Portuguese added.

"At this stage of the season, winning without suffering and without much effort is the most positive thing."

Barca, who beat arch-rivals Real 3-1 at the Bernabeu in December but have otherwise suffered patchy away form, can trim the gap to 10 points with a win at home to third-placed Valencia on Sunday.

Benzema said the comfortable win was ideal preparation for the Champions League last-16 first leg at CSKA Moscow.

"It was a great game for us tonight and now we'll try to do the same on Tuesday," said the French international.

In the earlier kickoff, Espanyol climbed above Levante into fourth place despite surrendering the lead in a 1-1 draw at Getafe.

Espanyol have 33 points, one ahead of Levante who host Rayo Vallecano on Sunday. Sevilla ended a run of three straight defeats and eight games without a win when they beat Osasuna 2-0, a first success for new coach Michel. Gary Medel netted the opening goal in the 16th minute at the Sanchez Pizjuan and substitute Piotr Trochowski scored in added time.

The Andalusian club moved to 10th as their bid to qualify for Europe next season gets back on track. Osasuna, who beat Barca 3-2 at home last weekend, are eighth on 31 points.