Barcelona take on Valencia in the early kick off knowing that any dropped points at Camp Nou is likely to let Real Madrid right back into the title race.
It's the toughest of tests for Luis Enrique's men coming on the back of an equally draining assignment at Sevilla a week ago.
The men from Mestalla have reasons of their own for needing all three points. They remain just one place and one point behind Atletico Madrid in the race for the automatic Champions League spot with Sevilla breathing down their necks just three further points back.
Let's take a look at three things that could shape the outcome of this game...
We've been here before haven't we.
For reasons unknown at this stage, Barcelona just can't seem to get themselves into gear for the 4pm local kick offs on a Saturday.
Their performances in that slot have been well below par, with Getafe, Real Valladolid and others taking full advantage.
Los Che came to Camp Nou last year more in hope than expectation, but were good value for their eventual 3-2 victory.
Nuno Santo has Champions League football in mind and will still be smarting from Sergio Busquets' 94th minute winner at Mestalla earlier in the season, in a pulsating clash.
Negredo to cause problems
The Catalans will need to be wary of a revitalised Alvaro Negredo.
Often used as an impact sub, Negredo's power and strength in the air is exactly what Nuno Santo will be looking for as Valencia go all out to disrupt Barcelona's free-flowing game.
Negredo will have to work as hard as he's ever done in closing down Barca's central defenders.
Allowing Gerard Pique or Javier Mascherano to stroll out of defence and set up another Barca attack will render much of Negredo's role moribund, so he must be ready to put in the hard yards in order to reap the rewards.
Barca ignore him at their peril.
Xavi to start?
Although the back injury that Andres Iniesta received in the match with Paris Saint-Germain isn't thought to be too serious, taking him out of the firing line for one game might not be such a bad idea.
His replacement, Xavi Hernandez, managed more passes than every PSG player despite the limited time he was on the pitch, and Barca could do with that kind of midfield orchestration here.
Age it seems has not wearied him, and if Barcelona want to control long periods of this one then it's imperative that Xavi plays.
Ivan Rakitic can play further forward with ease, so there's no compelling reason why Luis Enrique should leave him on the bench.