Carlo Ancelotti 'not losing sleep' over improved Barcelona ahead of Clasico
Hansi Flick's Barca visit the Santiago Bernabeu sitting three points ahead of the second-place Spanish champions and thrashed German giants Bayern Munich 5-1 in the Champions League on Wednesday.
However Real Madrid are unbeaten in 42 La Liga matches and can match Barcelona's all-time record of 43 if they avoid defeat.
"The truth is they are doing very well," admitted Ancelotti at a news conference Friday.
"In a game like the Clasico, a derby, it's hard to pick a favourite.
"Luckily nobody is taking any sleep away from me at the moment."
Barcelona struggled last season and Madrid beat them in both La Liga Clasicos.
Madrid midfielder Jude Bellingham scored three times in those two games during a fantastic campaign, but this season has not found the net in his first 10 appearances across all competitions.
Ancelotti said he was happy with Bellingham's performances and that the onus was now on superstar striker Kylian Mbappe to lead the scoring charts for Los Blancos.
Bellingham, playing up front at the start of last season after Karim Benzema's departure, scored 10 goals in his first 10 Madrid matches.
"Last year we had no striker, we lost an important striker like Karim, we replaced him with the goals of Bellingham, Joselu and Brahim (Diaz)," continued Ancelotti.
"This year we don't have a problem, because we have a striker that can score 30, 35, 40 goals.
"The important thing is (Bellingham) does his work, which is very important."
Mbappe, who arrived from Paris Saint-Germain this summer, is preparing for his first Clasico and Ancelotti said the striker was relaxed.
The forward is engaged in a battle with former club PSG over 55 million euros (£45.8m) in allegedly unpaid salary and was recently criticised in France after not playing in Nations League matches for his country.
Reports emerged in Sweden he is being investigated for an alleged rape during a visit to Stockholm earlier in October, which Mbappe described as "fake news".
"His way of managing, preparing for games, is a very calm and simple way," said Ancelotti.
"He's played Barca many times, he knows what he has got to do."