Barcelona and Real Madrid both dropped points on their travels in La Liga, while Malaga defeated Rayo Vallecano and Levante edged out Sevilla.
Lionel Messi again made history but his goal was not enough to earn Barcelona a win over relegation-threatened Celta Vigo as their showdown ended in a 2-2 draw.
The Argentina international is no stranger to treading new ground and his 73rd-minute goal meant he has scored in 19 successive Primera Division matches.
In doing so he has found the net against every other side in the competition - the first player to ever do that in consecutive matches - and he has 29 goals from his last 19.
It would not be the winner, though, with Borja Oubina's late header earning Celta a point, with Naxto Insa's opener having been earlier scrubbed out by Cristian Tello's goal.
Real Madrid missed the chance to make things slightly less comfortable for Barca at the top of the standings as they were held by relegation-fighting Real Zaragoza at La Romareda
Madrid could have trimmed their arch rivals' lead to 11 points if they could beat Zaragoza and claim a seventh successive league victory
However, like Barca, they had to settle for just a point with Rodri putting Zaragoza ahead early on before Cristiano Ronaldo levelled things up just before the break with his 28th La Liga goal of the campaign.
Neither side could go on to force a winner in the second half, with Marcelo hitting the post for Madrid and both goalkeepers making a number of vital interventions.
Malaga temporarily reclaimed fourth spot with victory at Rayo Vallecano.
Weligton gave Manuel Pellegrini's side the lead but Piti levelled for the hosts from the penalty spot.
Former Real Madrid forward Julio Baptista scored his first goal in 18 months to restore Malaga's lead early in the second half before Pedro Morales secured all three points with a wonderful goal.
Levante edged out Sevilla in the battle of the two mid-table teams with Ruben Garcia scoring the only goal of the game with a low strike from outside the box in the 40th minute.