Thomas Tuchel's transformation of Chelsea's defence was the key to their stunning turnaround in fortunes following Frank Lampard's dismissal, according to former Blues midfielder and assistant head coach Eddie Newton.
Lampard was sacked on January 25 after a run of just two wins in eight Premier League games left Chelsea ninth, 11 points off the summit.
Former Paris Saint-Germain boss Tuchel was swiftly appointed and oversaw an impressive second half of the season, culminating in a stunning 1-0 win over Manchester City in the Champions League final on Saturday, Kai Havertz scoring the decisive goal shortly before half-time.
Tuchel also sealed a top-four finish for Chelsea and guided them to the FA Cup final, although they ultimately lost that to Leicester City.
Lampard and Tuchel were both in charge for 30 games across all competitions in the 2020-21 campaign, with the Blues conceding just 16 under the German compared to 31 in their former manager's games.
And Newton, who played for Chelsea between 1990 and 1999 and had spells as assistant head coach in 2012 and 2015-16, is in no doubt the success is down to Tuchel's work on remodelling the backline.
I don't believe that anybody feels the way I do about you now. pic.twitter.com/VpMfvSiGeA— Champions of Europe (@ChelseaFC) May 30, 2021
"Frank wanted to be on the front foot and the team was fundamentally in his personality," Newton told Stats Perform.
"He's a very offensive-thinking person, which leaves gaps at the back and towards the end they were getting punished on a regular basis. What Tuchel has done is put right the defensive side.
"He's also brought back senior players into the fold that were not in favour under Frank. Seniority brings stability and more nous about how to get through games when you're struggling. He brought that in.
"He changed the formation by playing three defenders at the back. It became multi-faceted.
"It's been fantastic stuff since he's come in. He's grabbed the bull by its horns and put down the foundations of what he wants to do.
"He's giving clear, concise information to everyone. Getting the results that he has, the players have bought into him. You can see the fight and that comes from the belief the coach has instilled into that team."
Tuchel once again chose Timo Werner to lead the line against City despite the Germany international's struggles in front of goal this season.
He arrived from RB Leipzig last June for a fee in the region of £45million (€50m) with a reputation of being one of the most prolific attackers in Europe.
Werner scored 34 goals and supplied 12 assists in 45 appearances in all competitions for Leipzig in 2019-20, departing as the club's all-time leading scorer with 95 goals in total.
He has not been able to scale the same heights in his maiden campaign in English football, though, the 25-year-old scoring 12 times in 52 appearances across all competitions. He finished the Premier League season with a shot conversion rate of just 7.59 per cent.
While Newton is impressed with Werner's work ethic, he believes Tuchel will need to sign an established central striker for the 2021-22 campaign, with Chelsea having been linked to Harry Kane and Erling Haaland.
"He hasn't played with a number nine," Newton said. "Werner's work rate, even though he's not been clinical in front of goal, is what he admires and I'm sure his team-mates do as well.
"He's willing to commit for the team. He's selfless, unlike other strikers, and works immensely hard for the team and that's where their defending starts from. It makes it easier for the team to defend.
"It's going to be interesting to see what he does next season. They can't continue without a number nine. Havertz is not a nine and won't be happy playing there. Werner is not a natural number nine; he likes to come in off the left and right.
"It's going to be interesting to see how Tuchel addresses that situation. If they bring in a number nine, where do you put Havertz and Werner?"