Barcelona have taken 40 points from 16 league matches and hold a four-point advantage over second-placed Real Madrid, who have won only two of their last eight games in all competitions. Despite the gap, Flick has said complacency could quickly undo their work.
"It's a long road ahead," Flick said. "It's December, and we've got a lot to play for. The important thing is to look at ourselves. There are things we can do better. The right attitude is not to be happy with what we've already got. We have to keep going.
"At the end of the season, that's what will put you in your place. That's when you'll have earned what you've got."
Barcelona are preparing to host 15th-placed Osasuna on Saturday with confidence growing after four consecutive victories in all competitions. Their run includes a 2-1 comeback win at home to Eintracht Frankfurt in the Champions League on Tuesday, a match that marked the return of Raphinha and Pedri, both of whom played decisive roles.
Despite positive results, Flick has continued to face questions about his goalkeeping hierarchy. Marc-Andre ter Stegen, 33, was named in the squad against Frankfurt but remained on the bench and has yet to play this season after suffering a back injury in July.
Ter Stegen later became involved in a dispute with the club after declining to sign a long-term medical leave agreement that would have helped Barcelona manage their finances under La Liga regulations, leading to him being briefly stripped of the captaincy.
In his absence, Joan Garcia has established himself as the clear first choice. The 24-year-old, signed from Espanyol in the close season, has made 13 appearances in all competitions.
"Joan is number one," Flick said. "I'm not going to talk about the number two or three goalkeeper. Joan plays, we believe in him, and I have no intention of replacing Joan. He has done very well."
Flick also declined to comment on Real Madrid's struggles or the pressure facing their coach Xabi Alonso ahead of Sunday's trip to Alaves.
"I'm not worried about Real Madrid," Flick said. "Only about ourselves and our current situation."
Atalanta coach Raffaele Palladino has said Tuesday's Champions League last‑16 tie against Bayern Munich promises to be a "magical night" and insists his team will fight hard despite a difficult injury list.
Diego Simeone has been clear about one thing before Atletico Madrid's Champions League last‑16 first leg against Tottenham Hotspur: he does not see his side as clear favourites.
Newcastle United manager Eddie Howe has challenged his squad to seize a once‑in‑a‑lifetime opportunity by beating Barcelona in their Champions League last‑16 first leg at St James' Park on Tuesday.
Vincent Kompany has remained cautious over Harry Kane's fitness ahead of Bayern Munich's crucial UEFA Champions League Round of 16 clash against Atalanta on Tuesday night, insisting a final decision will be made on matchday morning.
