The title is usually a straight race between the two traditional rivals, the ever-widening economic gap between them and the rest of the league a matter for on-going concern.
Real pushed out the financial boat to snare Mourinho, after his treble-winning exploits with Inter Milan last season, and have also spent 75 million euros on new players.
While Cristiano Ronaldo and Kaka were marquee signings in last year's 250 million euro reinforcement programme, this year's top acquisition is 'The Special One' Mourinho as a replacement for the trophy-less Manuel Pellegrini.
Six new players join him including Argentina's Angel Di Maria and German duo Sami Khedira and Mesut Ozil, the focus being on youngsters hungry to make a mark rather than established names.
Out have gone long-serving stalwarts Raul and Guti, breathing new life into the Bernabeu dressing room. The message is clear... this is Mourinho's Madrid.
Last year Real finished three points behind Barca, defeats in the two 'clasicos' the main difference between the teams as they both established record points totals.
"Barca are a finished project, they can play with their eyes closed. Real Madrid aren't there yet," he told reporters. "Real need to establish a new way of playing football and a different philosophy."
Barca's preparations have been disrupted by a change in president, Sandro Rosell replacing Joan Laporta, concerns over the club's finances, and they have been clumsy in the transfer market especially with a failed bid to land Cesc Fabregas from Arsenal.
Spain striker David Villa's signing from Valencia for 40 million euros is money well spent but the exits of Thierry Henry, Dmytro Chygrynskiy, Rafael Marquez and Yaya Toure have yet to be fully addressed.
Guardiola has said he will rely on versatility within his squad and the youth system. That is fine as long as Messi and Xavi can avoid injury because Barca's squad looks thin.
They have managed to hang on to leading strikers Diego Forlan and Sergio Aguero and have reinforced their Achilles heel, the defence, by signing Uruguay's Diego Godin and Brazilian full back Felipe Luis.
