On Saturday night, Juventus took on city rivals Torino in the Derby della Mole.
Miralem Pjanic had been a doubt for the game with a minor thigh muscle problem.
Not only did he start, though, he played all 90 minutes.
Pjanic has become that important to Juventus. He has become Maurizio Sarri's new Jorginho.
Injuries and the make-up of the squad have forced the Tuscan trainer into moving away from his beloved 4-3-3 formation in Turin – for now at least – but the need for a deep-playing playmaker to dictate the pace of the game remains utterly integral to 'Sarriball'.
And nobody can perform the role better at Juventus than Pjanic.
Rodrigo Bentancur tried against Genoa last Wednesday but while the Uruguay international has many attributes, he does not exert anything like the same control over the game as his Bosnian team-mate.
In the end, Juventus only prevailed thanks to the harshest of penalties won and converted by Cristiano Ronaldo in the seventh minute of injury time.
Sarri pointed out afterwards that Juve's problems were twofold.
Firstly, without Gonzalo Higuain, who also missed the game through injury, Juventus did not have a point of reference in attack.
The Argentine is, of course, a long-time Sarri favourite but the coach is correct when he says that Higuain is the only striker at Juventus with "the characteristics of a real centre-forward.
"The others are more atypical. Despite dominating possession, we always risk not having enough presence in the box without Gonzalo."
However, of greater significance was the absence of Pjanic, as Juve looked slow and predictable in possession without him.
"We missed his quality, of course," Sarri explained, "but also his rhythm, because he moves the ball fast and our play becomes quicker as a result."
Pjanic has always been an influential player at Juventus, of course, but there were always doubts over whether he was the right man to play at the base of midfield in Massimiliano Allegri's teams.
And maybe he wasn't. But he is the right man to play there in a Sarri side.
He has been asked to perform the Jorginho role and is doing it exceptionally well.
The only midfielders to have made more successful passes or had more touches than Pjanic in Serie A this season are Marcelo Brozovic and Fabian Ruiz, and both have played significantly more minutes than the Bosnia international.
The remarkable thing, though, is that Pjanic is also enjoying one of the most productive periods of his career.
Jorginho, of course, is renowned for rarely scoring in open play yet Pjanic has already struck three times in just 10 outings – and not one of those goals was a set-piece special.
Pjanic spoke glowingly of Allegri when the former Bianconeri boss departed at the end of last season but he has, unsurprisingly, been barely able to contain his delight at how Juve's play – and his role within in it – has changed this term.
"Playing under Allegri was completely different, as we immediately looked to get the ball wide," he explained.
"Now, it’s different. My team-mates always look for me and I like that.
"It all depends on what the coach asks of me but I play more passes and now I want to touch the ball 150 times per game."
This is arguably a more confident Pjanic than we've ever seen before and that's manifested itself in him demanding that others do their jobs as well as he has been doing his.
Indeed, on three separate occasions this season, Pjanic has called out Juve's attackers for not being "incisive", "ruthless" or "clinical" enough in attack.
Juventus remain undefeated, both domestically and in Europe, and currently sit at the summit of the Serie A standings with nine wins from 11 games.
However, they have netted just 19 goals in the league, which is less than every other team in the top five: Inter (24), Roma (20), Lazio (24) and Atalanta (30).
Sarri himself has acknowledged that his primary strikers – Ronaldo, Higuain and Paulo Dybala – have yet to find their shooting boots.
"We have a very low average of shots finding the net," the former Chelsea boss said last week. "In my view, it’s more of a mental issue than anything else.
"I expressed my fear with the players about that and we’ll try to prepare some training exercises to help, but we also need to be more determined in front of goal."
Ronaldo, unsurprisingly, is Juve's top scorer – yet he has netted just six goals, two of which were penalties.
The Portuguese will, of course, ultimately prove integral to Juve's twin hopes of ending their Champions League drought and getting the better of Inter in an increasingly fascinating Scudetto race.
However, right now, with Ronaldo not in form, and with captain Giorgio Chiellini out of action, it is Pjanic who is proving Juve's most important player.