Juventus relied too heavily on Cristiano Ronaldo over the past three seasons, Leonardo Bonucci suggested after Wednesday's Champions League win over Zenit.
Ronaldo joined Juve in 2018 and helped the Bianconeri win Serie A twice, though they fell short of winning a 10th straight Scudetto last season.
The 36-year-old left Juve in August, heading back to Manchester United in a shock transfer. He hit the ground running at Old Trafford and, after going two games without a goal, scored the winner in the Red Devils' 3-2 comeback victory over Juve's fellow Serie A side Atalanta midweek.
While Ronaldo spearheaded United's attack in Manchester, Juve moved onto nine points in Champions League Group H as Dejan Kulusevski's 86th-minute header sealed a 1-0 win over Zenit.
It is the first time Juve have won all three of their opening Champions League group-stage matches since Massimiliano Allegri's last season in charge, back in 2018-19.
Though they have made an impressive start in Europe, Juve have laboured in the league and sit seventh heading into Sunday's derby d'Italia clash with Inter, though a win would take them onto level points with the defending champions.
Ronaldo scored 36 goals in all competitions last season, with only four players across Europe's top-five leagues managing more, but Bonucci believes Juve lost a will to "suffer and sacrifice".
"It's absolutely true, it is what we all said," Bonucci told Sky Sport Italia after the win in St Petersburg. "In the recent past, we had lost that characteristic of Juve.
"We were all playing with a great champion and wanted him to do well, so perhaps we lost that desire to all suffer and sacrifice ourselves together, because we assumed he would sort it out.
"The coach has done really well to get that spirit and humility back and we all work together now to get the result."
While Juve may have their spirit back, they did lack cutting edge for a significant portion of Wednesday's match.
Weston McKennie had passed up two previous opportunities, including what was the best chance of the game, as per Opta's expected goals (xG) value, when he saw a close-range effort saved by Stanislav Kritsyuk in the 51st minute.
Kulusevski eventually broke the deadlock when he glanced Mattia De Sciglio's cross in off the post to become Juve's second-youngest Champions League goalscorer, after the great Alessandro Del Piero.
"I will never forget this goal for as long as I live," Kulusevski told Juventus TV. "It was my debut Champions League goal, the first I have scored this season and it was even a header!"
Juve's cause in attack might have been helped by Paulo Dybala, but the Argentine forward, whose next Champions League appearance will be his 50th in the competition, was unavailable due to an injury he sustained last month.
Before the match, vice-president Pavel Nedved revealed talks over a new deal are almost resolved.
Nedved told Sky Sport Italia: "We all hope he can be on the pitch and sign the new contract. I believe we are very close to the signature, we're very happy. Paulo is very important for this team."