The Spanish giants Real Madrid and Barcelona have been dominant figures in the world of football for decades, with their success in Europe unmatched by any other team. In the La Liga's Champions League group stage, these two clubs have consistently dominated their opponents, leaving little room for anyone else to compete.

Real Madrid has had a particularly impressive record in recent years, winning three consecutive UEFA Champions League titles between 2016 and 2018. The club's dominance is evident in its performances in the group stage, where they have consistently emerged victorious against teams such as Juventus, Bayern Munich, and Paris Saint-Germain. In the 2020-2021 season, Real Madrid won the group stage with ease, finishing top of the standings after a perfect run of six wins out of six games.

Barcelona, on the other hand, has also enjoyed significant success in the Champions League, winning the tournament four times since 2015. Their dominance is even more impressive when compared to Real Madrid, with the Catalan club having won the competition twice in a row from 2017 to 2019. In the 2020-2021 season, Barcelona finished second in the group stage behind Real Madrid, but still managed to secure a spot in the knockout stages thanks to their superior goal difference.

Despite their dominance in the group stage, both Real Madrid and Barcelona will face tough competition in the knockout stages. They will need to perform at their best if they want to progress further into the competition. However, given their track record, it is safe to say that these two clubs will be among the favorites to win the tournament once again.