Juan Mata has named Didier Drogba as the best team-mate he played alongside in the Champions League, while Lionel Messi is the Spaniard's most revered opponent.
Drogba, a legend at Stamford Bridge, scored the winning spot-kick in Chelsea's penalty shoot-out victory over Bayern Munich in the 2012 Champions League final.
It brought up Chelsea's first European crown, one they followed up nine years later by beating Manchester City 1-0 in Porto.
Drogba's coolly taken penalty was his memorable final contribution during his first stint at Chelsea, albeit he returned for a brief second spell in 2014.
Mata, who now plays for Galatasaray, had left for Manchester United by that time, but for him, Drogba will always be the former team-mate synonymous with big Champions League moments.
"If I think about the Champions League, and the times we played together at Chelsea, and when we won the competition, the first big man that comes to mind is Didier Drogba," Mata said in an interview with the Go Turkiye YouTube Channel.
"He scored the goal in the final, he scored the last penalty, he was a leader on and off the pitch, and he is definitely one of the best strikers of the last 20 or 30 years, so he has to be there.
"He was very helpful to me during my time in London, and he comes to my mind when I think of the Champions League.
"I also have to mention John Terry, [Frank] Lampard, Wayne Rooney, [Robin] van Persie, and many other greats that I had the chance to play with.
"But when I think of Champions League and that final in Munich, it has to be Didier."
When it came to the toughest opponent playmaker Mata has faced, there was only one player who came to mind.
"I'll have to go with Messi," Mata said. "I played against him in the Spanish league with Valencia, but also in the Champions League with Chelsea.
"I remember those semi-finals when we won it, and he missed a penalty, and he was very unlucky.
"But he is an unbelievable player, still playing at such a great level, we got to see what he did at the World Cup.
"I admire him, and it was a pleasure for me to play against him, hopefully we can play against each other again.
"For me, I have to say he is the one."
Hamit Altintop, who played for Bayern and Real Madrid, echoed Mata's sentiment, though it was not as easy for the former Turkey international to pick out an individual.
"Didier is a real leader on and off the pitch, I played with him in Galatasaray," he added.
"One of my friends asked me if I could make my best XI. In goal: Oliver Kahn, Manuel Neuer, Iker Casillas… These names are all unbelievable players that get mentioned if you talk about the Champions League.
"Iker Casillas is amazing, Cristiano [Ronaldo] the same, if you're talking about the Champions League, you have to mention Messi, of course. All of these names come to mind."
An Italian team is guaranteed to reach the Champions League final for the first time since 2017, when Madrid beat Juventus, with a Milan derby on the cards in the semi-finals.
Manchester City and Madrid face off in the other semi-final tie, and Mata pointed out it is not always the strongest team that goes on to win the competition.
"Sometimes in the Champions League, the best teams don't win, because it's not as long as a normal league, so sometimes you need a little bit of luck: a post, a save, a penalty or other things like that," the 34-year-old said.
"If you don't have mental strength, and if you don't all behave as one, you're not going to win. I felt like that is what happened with Chelsea at that time, we felt like it was meant to be, we felt that was the year.
"For me the mental aspect of football, sometimes it is undervalued, but for me it is key."