Carlo Ancelotti has rejected claims Real Madrid have been fortunate in recent Champions League campaigns, insisting "you have to do everything well" to prevail in Europe.
Ancelotti led Madrid to their 14th European crown last season, and Los Blancos have made a perfect start to their Champions League defence, topping Group F following wins over RB Leipzig and Celtic.
Madrid repeatedly defied the odds en route to last season's triumph, losing a match in each of their first three knockout ties (against Paris Saint-Germain, Chelsea and Manchester City).
But speaking ahead of Wednesday's clash with Shakhtar Donetsk, Ancelotti – the only coach with four European titles to his name – said fortune can only take a team so far.
"I always want to win the Champions League. The league is very important, but the Champions League is the most important competition," he said.
"They are different. One is 38 games and the other is much less. Sometimes it's a 180-minute tie. That's where the little details matter.
"It's not luck or bad luck. Sometimes talking about luck hides the problems that you have and the merit of the rival.
"If I say that we had bad luck against Osasuna [in Sunday's 1-1 draw], it means that I hide the problems we had with the ball, and the good performance of the rival.
"Talking about small details is important, in the Champions League, you can score three goals in a few minutes, as has happened to me. It can also happen to you in a semi-final.
"Small details are controlled with a very strong mentality. Real Madrid has been the team that has taken the most care of these details.
"Everyone has their opinions. Football is made of many things. In the Champions League, you have to do everything well, I think the best team wins the Champions League.
"I think the history and tradition of this club plays a part in the way we play. It's not luck or good fortune that this team has such extraordinary success in this competition."
Meanwhile, Ancelotti offered an update on the conditions of Thibaut Courtois and Luka Modric after both players missed Sunday's draw with Osasuna through injury.
While Courtois will not feature on Wednesday, Ancelotti is certain he will return for their huge Clasico meeting with Barcelona in LaLiga, which takes place in less than two weeks.
"He's much better, he received some treatment yesterday," Ancelotti said of the Belgium goalkeeper. "We have to wait and see if he can play against Getafe [on Saturday], but he should definitely be ready for the return fixture against Shakhtar and El Clasico.
"Lucas Vasquez and Luka Modric have both trained with the team."
However, when pressed on Modric's availability for Wednesday, Ancelotti added: "I doubt if he will start."
Madrid have won four of their six Champions League matches against Shakhtar, although they suffered two defeats against the Ukrainian outfit in the 2020-21 campaign.