Blaugrana manager Xavi watched his side concede three goals at home to Inter Milan earlier this week, leaving their UEFA Champions League hopes hanging in the balance.
Ronald Araujo is missing and the club could rush Jules Kounde back into action or Sunday’s trip to the Bernabeu, such is the lack of options at the back.
Hector Bellerin and Andreas Christensen are also doubts, meaning Gerard Pique could be called up despite his poor performance against Inter.
While Frenkie de Jong and Franck Kessie are available, Memphis Depay is injured ahead of the LaLiga top-flight decider.
Both sides are unbeaten in the domestic sense, but a loss for either would be a huge blow. If Xavi in particular succumbs to defeat, the pressure would only increase after a bad week.
Thibaut Courtois is expected to miss the game following his recent nerve injury, with Andriy Lunin on standby. Antonio Rudiger trained in at least some capacity, but Eder Militao and David Alaba provide adequate cover in central defence.
Federico Valverde will almost certainly start on the right of the attack and Ancelotti’s side largely picks itself.
Karim Benzema is fit again and could be up against a Barca defence who are only just welcoming summer signing Jules Kounde back into action.
Real Madrid vs Barcelona prediction
With both teams yet to taste domestic defeat this season, the stakes are high even at this early stage.
For that reason, expect it to be cagey.
Barcelona predicted XI vs Real Madrid (4-3-3):
Ter Stegen; Roberto, Garcia, Pique, Alonso; De Jong, Pedri, Kessie; Dembele, Lewandowski, Raphinha
Real Madrid predicted XI (4-3-3):
Lunin; Carvajal, Militao, Alaba, Mendy; Tchouameni, Kroos, Modric; Valverde, Benzema, Vinicius