Carlo Ancelotti acknowledged it will be "difficult" for Real Madrid to win LaLiga after Los Blancos were forced to fight back in a frustrating 1-1 draw with 10-man rivals Atletico Madrid.
Madrid would have fancied their chances of moving within five points of leaders Barcelona when Atleti substitute Angel Correa was controversially sent off with Saturday's derby poised at 0-0.
Atleti then looked set for a memorable win when Jose Gimenez headed them in front at the Santiago Bernabeu, only for 18-year-old forward Alvaro Rodriguez to spare Madrid's blushes late on.
With the stalemate handing Barcelona the chance to go 10 points clear when they visit Almeria on Sunday, Ancelotti is aware of the size of Madrid's task.
Asked about the title race by DAZN, Ancelotti said: "It was already very difficult before this match, now it's more. We are going to fight until the end, that's what I can say.
"We lacked a bit of freshness. But mentally more than physically. At 1-0, it took us 10 minutes to compose ourselves, to reposition ourselves.
"In the first half there was a lack of intensity and in the second, we reached it at the end, but we didn't fully take advantage of the numerical superiority."
However, Ancelotti did reserve praise for Alvaro, who became the youngest player to score in a Madrid derby in LaLiga this century (aged 18 years and 226 days).
"It was very important for him, a young man with an enormous dream of playing for Real Madrid," Ancelotti said of the Uruguayan forward. "This will be a special night in his life."
Alvaro's 85th-minute header denied Diego Simeone a famous victory on the day he matched Luis Aragones' record tally of 612 games in charge of Atleti, and the Colchoneros boss opted to focus on Correa's red card – issued for an innocuous push on Antonio Rudiger – in his post-match interview.
"Those who have played know that contact is not always a blow. Rudiger is 1.94 metres tall and such a brutal blow left him sitting down… then he immediately gets up," Simeone told DAZN.
"It may be a yellow, but taking out a player for that... there would be no players left on the field.
"It repeats itself, it is becoming normal and that is not right, and it would be nice if we could all compete in the same way.
"I think that VAR exposes errors much more. Every time we come here, it is never our turn to be in favour."
The result saw Atleti halt a run of three successive league defeats at the home of their cross-city rivals, though Madrid have now lost just one of their last 14 matches against Los Colchoneros in LaLiga (W6 D7).