Madrid were held to a goalless home draw by Osasuna while Sevilla couldn't manage more than a 1-1 result at Real Mallorca.

Real Betis joined the Madrid and Sevilla on 21 points by dispatching Valencia 4-1 while Real Sociedad can move clear at the top with a favourable result against Celta Vigo on Thursday.

"We wanted to take advantage that Barcelona lost and Sevilla drew, but it wasn't possible," Madrid defender Dani Carvajal said.

"We tried everything but the ball wouldn't go in."

Madrid were coming off a win over Barcelona in the clasico at the Camp Nou on Sunday.

The Catalan club's struggles continued in a 1-0 loss at Vallecano, with veteran striker Radamel Falcao scoring the winner in the first half.

Barcelona's second consecutive defeat left them winless in away matches and only ninth in the standings with 15 points from 10 games.

The defeat also cost Ronaldo Koeman his job with the club announcing hours later that the Dutch coach had been sacked.

It was the fifth straight home win for promoted Rayo, who moved to fifth place with 19 points from 11 matches.

Wednesday's victory was their first over Barcelona at home in nearly two decades.

"This victory means a lot to us," said Falcao, who had not defeated Barcelona while he played for Atletico Madrid in the early 2010s.

"We are glad that we are giving our fans a chance to enjoy something they had never been able to enjoy before."

Barcelona missed a second-half penalty when forward Memphis Depay had his shot stopped by Rayo goalkeeper Stole Dimitrievski.

"This is what has been happening to us during most of the season," Barcelona midfielder Sergio Busquets said.

"We are missing a little bit of everything. We need a little bit more luck, belief, concentration, to make less mistakes..."

Barcelona had not gone five consecutive away matches without a win in nearly 20 years.

Australian Associated Press