Master Ancelotti shows pupil Conte how it's done
Bayern coach has the upperhand over Chelsea manager, who was his former player at Juventus
One is a bundle of high energy - screaming, clapping, grimacing and thumping his chest as he patrolled the touchline within the Chelsea technical area.
The other carried the dignified air of an elder statesman - hands on waist, quietly taking it all in while chewing his gum.
And that's when the silver-haired coach is not chilling out in the Bayern Munich dugout.
Last night, two of the world's top managers clashed tactically at the National Stadium and it was wily master tactician Carlo Ancelotti who showed his former player Antonio Conte the ropes once again.
In front of 48,522 fans, Ancelotti's Bayern Munich beat Conte's Chelsea 3-2 in the opening match of the International Champions Cup in Singapore.
The Italian pair go back a long way, as displayed by the firm handshake and affectionate hug at the final whistle.
Near the turn of the millennium, Conte was a tenacious midfielder approaching his 30s and at the peak of his illustrious playing career with Juventus when Ancelotti took the helm in 1999.
It turned out to be a largely barren two-and-a-half seasons, remembered for an Intertoto Cup win in 1999 and also a dramatic collapse on the domestic front in 2000.
But Conte had seen enough of Ancelotti and described him as "the best Italian coach".
Yesterday, he reaffirmed his admiration and told The New Paper at the post-match press conference: "I was very lucky to have Carlo as my head coach at Juventus even though we were unlucky not to win any major trophy.
"For sure, Carlo is one of the best managers in the world and I have been lucky to learn from great managers like Marcello Lippi, Arrigo Sacchi and Giovanni Trapattoni.
"It's very difficult to put into words what it is that I learn from each of them but, for sure, Carlo had a big influence on me."
That's high praise from the 47-year-old, whose transition from player to coach has looked as seamless as Ancelotti's.
Over the last 12 years, Conte won three Serie A titles with Juventus, took charge of the Italian national team from 2014-16, and led Chelsea to the English Premiership crown last season.
Such success has inevitably drawn comparisons between Conte and the 58-year-old Ancelotti, himself a serial winner in Italy, England, France, Spain, Germany, and also three times in the Champions League during a 23-year span.
The mutual respect was evident after yesterday's clash, as Ancelotti, himself heavily influenced by his former coach Sacchi, said: "When Antonio was my player, he was really good tactically on the pitch, with a strong personality and a strong character. He was a great professional.
"He shows his character as a manager. When Chelsea play, I recognise it's a team of Antonio."
While Ancelotti's early coaching days at Juventus would have inevitably rubbed off on Conte, it was clear from last night's match that their styles were as different as chalk and cheese.
Ancelotti's picture of composure on the sidelines contrasted starkly with Conte's manic intensity. What they share is an impressive tactical nous and a winning mentality.
For now, it is Ancelotti who holds the aces as he remains unbeaten in three meetings against Conte. The former's Real Madrid had beaten the latter's Juventus 2-1 before a 2-2 draw in two Champions League matches in 2013.
But Conte's fiercely competitive streak suggests that this intriguing master-pupil series is far from over.
With a glint in his eye and a sly smile, he said: "We shall see."