On Sunday, Real Madrid defeated promoted Almeria 2-1 to begin the defense of their La Liga championship after giving up an early goal.
Ancelotti made five adjustments to the squad that defeated Eintracht Frankfurt in the Uefa Super Cup final on Wednesday, including the debuts of newcomers Aurelien Tchouameni and Antonio Rudiger.
However, Almeria were not about to submit to the Spanish and European champions and took the lead in the sixth minute thanks to striker Largie Ramazani.
As a result of Vinicius Jr. and Fernando Martinez's personal dispute, the Almeria goalkeeper made three vital close-range saves to deny the Brazilian forward for Real.
Karim Benzema, who led La Liga in goals scored last season, had a disappointing performance as Almeria's five-man defense did an excellent job of containing him and displaying real grit in their attempt to defend their lead.
Real piled on the pressure after the break when Ancelotti summoned veteran midfielder Luka Modric and winger Eden Hazard from the bench in place of young French midfielders Eduardo Camavinga and Tchouameni, who struggled to make an impact.
In the 61st minute, Lucas Vazquez scored the equaliser from a rebound after another individual effort from Vinicius, and substitute David Alaba scored the winner from a free kick into the upper left corner in the 75th minute.
“It was a complicated match; they explored very well the spaces that we left at the back of the defence,” Ancelotti told Movistar Plus.
“Tchouameni and Camavinga didn’t show their true quality and potential, but sometimes the Real Madrid shirt is a heavy burden for the young players."
“I have full confidence that they will progress because they are high-level players.”