Real Madrid lead the Spanish league after beating Villarreal 4-1 but lost defender David Alaba with a serious knee injury on Sunday.
Jude Bellingham, Rodrygo, Brahim Díaz and Luka Modric scored for Madrid, which moved one point ahead of Girona ahead of the Catalan club's home game against Alaves on Monday.
Madrid is seven points ahead of third-place Barcelona. The defending champion drew 1-1 at Valencia on Saturday.
"It's always good to open a gap to Barcelona," Rodrygo said. "But seven points is not a lot, there is still a lot of league left. We have to keep this mindset and keep trying to win every match."
Alaba had to be helped off the field at the Santiago Bernabeu before halftime when his left knee buckled while he tried to steal the ball from an opponent near midfield. The Austria defender fell and immediately called for help while grabbing his knee. He couldn't put weight on his left leg while being carried off the field in the 34th minute.
Madrid said after the match that Alaba ruptured the anterior cruciate ligament and will need to undergo surgery in the next few days. The club did not immediately say how long he is expected to be sidelined.
"He was sad at halftime," Rodrygo said. "We have to wait for the tests but it's something that worries us."
It was the latest serious knee injury for Madrid this season. The club is already without goalkeeper Thibaut Courtois and defender Éder Militão because of cruciate ligament injuries that are expected to keep them out of action for a long period. Eduardo Camavinga and Arda Guler also sustained knee injuries.
"We are very sad because it's the third injury like this in the last four months. It's something that had never happened to one of my teams before," Madrid coach Carlo Ancelotti said. "But the team has been able to overcome these injuries. It has done more than people thought it could do."
Bellingham and Rodrygo continued their good scoring runs to give Madrid a 2-0 first-half lead. Bellingham scored his league-leading 13th goal with a header off a cross by Modric in the 25th, and Rodrygo added to the lead in the 37th for his fifth goal in his last six games. Bellingham has seven goals in his last nine matches with the club.
Díaz scored the third goal after a beautiful run that started near the midfield line in the 64th. He cleared two defenders before finding the net from inside the area. Modric closed the scoring with another shot from inside the box in the 68th.
José Luis Morales scored in the 54th for Villarreal, which hasn't won in three straight league matches and has dropped to 14th place.
Villarreal has nine losses in 17 league matches so far, its worst run at this point of a season.
Villarreal had been the last team to beat Madrid in the league at the Bernabeu, winning 3-2 last season. That was Madrid's only loss in its last 31 league matches as a host. It lost both of its league matches against Villarreal last season.
Díaz started instead of Joselu, while Lucas Vazquez was the right back in place of the injured Dani Carvajal.
THRILLING DRAW
Sixth-place Real Sociedad had three goals disallowed and twice hit the woodwork in a 0-0 home draw against seventh-place Real Betis.
It was the ninth consecutive match without a loss for Sociedad in all competitions, and the third straight league draw for Manuel Pellegrini's Betis.
CADIZ HELD
Cadiz's winless run in the league reached 13 matches after a 1-1 draw at Las Palmas.
Cadiz, which equalized with a goal by Chris Ramos in the 83rd, stayed only one point from the relegation zone. Las Palmas, which was seeking its fourth win in a row in all competitions, is in ninth place.
ALMERIA STILL WINLESS
Almeria drew 0-0 with Mallorca at home to remain the only winless team after 17 rounds.
The Saudi-owned club has five draws and 12 losses. It is eight points behind the first team outside the relegation zone.
Mallorca, unbeaten in five straight games in all competitions, is in 15th place.
