London: Two of Europe's heavyweights go head-to-head in one of the ties of the round as Atletico Madrid welcome 2017 finalists Juventus on matchday one in the Champions League.
Maurizio Sarri takes charge of his first game in the competition after recovering from pneumonia, but facing off against Diego Simeone's tactically-sound Atletico could give the Italian a headache.
The Rojiblancos sit top of the Liga table after three wins from four games, though they did suffer a surprise 2-0 defeat away to Real Sociedad on Saturday.
Juve, meanwhile, stuttered to a goalless draw against Fiorentina at the weekend and that suggests all may not be well in the Bianconeri camp at present.
With Atletico sitting ahead of each of Real Madrid and Barcelona in the La Liga standings, Diego Simeone will be satisfied with how his much-changed team have started the new season.
Nevertheless, the Argentine would have been disappointed to see his side lose out 2-0 to Real Sociedad at the weekend, especially on the back of needing to overturn a two-goal deficit to get the better of Eibar in front of their own supporters.
Atletico still remain in second position in the table, just a point adrift of Sevilla, but there is little doubt that they must make improvements in order to register a positive result against Juventus.
That applies to all areas of the pitch, despite the likes of Kieran Trippier and Joao Felix both continuing to impress since their summer moves from Tottenham Hotspur and Benfica respectively.
However, Juventus will arrive in Spain also aware that they still need to go through a few more gears in order to repeat their success of previous seasons.
A return of seven points from their first three Serie A fixtures is a respectable return, especially when considering the dramatic showdown with Napoli at the end of August.
Nevertheless, failing to find the back of the net at Fiorentina and a mounting injury list has only given Maurizio Sarri more food for thought ahead of facing the La Liga giants.
Sarri will also want to see more from Cristiano Ronaldo, who has contributed just one goal this season ahead of his return to Madrid, a city where he spent nine hugely successful years with Real.