Claims that Carlo Ancelotti's men lost their balance with the close-season departures of Angel di Maria and Xabi Alonso have been strengthened by a spluttering start to 2014-15.
Having begun this term with a Supercopa de Espana loss to neighbours Atletico, the European champions appeared to be back on track when easing past Cordoba 2-0 in their La Liga opener.
The promise gleaned from that sparked a remarkable spell where they pulverised Real Sociedad early in their next fixture, moving 2-0 inside 11 minutes.
However, that game ended in a shock 4-2 defeat, made worse when Atletico - who they beat in the Champions League final last season - left the Santiago Bernabeu with a 2-1 triumph on Saturday.
Real can at least now turn their attentions to Group B of European club football's elite competition as the Swiss champions come to town.
Leading the line for Ancelotti's men will be Cristiano Ronaldo, who scored in the Madrid derby to suggest he has fully recovered from a knee problem.
However, there are injury concerns with Sami Khedira set to be sidelined through a hamstring complaint, while Dani Carvajal (thigh) and Jese Rodriguez (knee) are doubts.
The weight of history is against Real, who are aiming to become the first team in the Champions League era to retain the iconic trophy.
However, they will take heart from the record books in this game, having won all 10 of their homes games versus Swiss opposition, scoring 42 goals and conceding just two.
Basel, though, are one of the only teams to find the net versus Real at the Bernabeu, when the sides met in the 1971-72 UEFA Cup first round.
The Spanish giants came from a goal behind to win 2-1 in Switzerland before sealing a 4-2 aggregate success.
Basel have enjoyed a solid start to their campaign, collecting six wins from eight games to sit top of Super League - albeit having played a game more than second-placed Zurich.
However, they head to Madrid following a disappointing 3-1 loss at Grasshopper on Saturday.
That was their second loss of this term, with St. Gallen the only other team to beat them.
Basel, who were eliminated during the group phase of last season's competition, have never progressed beyond the round of 16, which they reached in 2011-12.
