Real Madrid suffered a 3-2 defeat at home against Shakhtar Donetsk in their Champions League Group B opener on Wednesday.
The Ukrainian side raced into a 3-0 lead in the first half with a strike from Brazilian midfielder Tete, an own goal from Madrid defender Raphael Varane and a fine goal from Israeli forward Manor Solomon.
Luka Modric and substitute Vinicius Jr score Madrid's consolation goals in the second half.
Inter Milan were held to a 2-2 draw by Borussia Monchengladbach in the other Group B encounter.
Elsewhere, in Group A, defending champions Bayern Munich crushed Atletico Madrid 4-0 with winger Kingsley Coman scoring a brace, while Salzburg and Lokomotiv played out a 2-2 draw.
In Group C, Manchester City beat Porto 3-1 and Olympiakos overcame Marseille 1-0.
Meanwhile, in Group D, Liverpool edged Ajax 1-0 and Italian side Atalanta thrashed Denmark's Midtjylland 4-0.
Saudi Arabia will host the FIFA World Cup in 2034 while the 2030 edition will be held in Spain, Portugal and Morocco, with one-off matches in three South American countries.
FIFA is set to confirm the hosts of the 2030 and 2034 men's World Cups on Wednesday, with a three-continent, six-nation bid led by Morocco, Spain and Portugal to be awarded the former and the latter going to Saudi Arabia.
Following arguably the most dominant year of golf since Tiger Woods was in his prime, Scottie Scheffler received the PGA Tour Player of the Year award on Tuesday night.
European Ryder Cup stars Robert MacIntyre and Tyrrell Hatton, and Major winner Adam Scott are the latest stars to confirm their return to the Hero Dubai Desert Classic, while PGA TOUR winner Akshay Bhatia will make his debut at the Emirates Golf Club from January 16-19.