Both of these teams reached the quarter-finals of the Copa Del Rey in midweek, with Athletic Bilbao squeezing past Espanyol 1-0, while Real Madrid managed to overturn a 0-2 half-time deficit to earn a thrilling 3-2 win at Villarreal.
This was a crucial victory for Carlos Ancelotti's team after a dip in form since the season reboot saw their 2-1 league defeat at Villarreal leave them three points behind Barcelona in the table.
It was then Barca themselves who outclassed Los Blancos in last weekend's Super Cup final in Riyadh, where the Catalans deserved their convincing 3-1 win.
Athletic Bilbao have also been struggling for form recently, with their last three La Liga outings yielding just two points from goalless draws with Real Betis and Osasuna.
Last week's 3-1 loss at Real Sociedad means they have now won just two of their last ten league outings, but nevertheless they sit eighth in the table, just two points behind the top four.
In their nine home La Liga games, Bilbao have kept six clean sheets, losing just twice to Espanyol and Atletico by the same 0-1 scoreline.
Their last three home games have brought wins against Villarreal (1-0) and Valladolid (3-0), along with that goalless draw against Osasuna.
No La Liga team has picked up more than Real Madrid's 21 away points (won 7, lost 2), but notably both defeats came in their last three games, 2-3 at Rayo Vallecano and 1-2 at Villarreal.
Real Madrid won both of last season's La Liga encounters with Bilbao, 1-0 at home and 2-1 away, and indeed they are undefeated in their last 14 league encounters against the Basque team, winning all of the last five.
Real Madrid boast the best attack in La Liga with 36 goals scored, while Bilbao are fourth with 25 goals.
The two teams are more evenly matched defensively, with Real Madrid conceding 16 goals so far to Bilbao's 17, but the eight clean sheets of the home team is second only to Barcelona's 12, and both teams will face a tough task in breaching their opponent's back lines.