Given his age—Fabregas is 28—the expectation should be that he still has five more seasons at the very top level before we can expect the natural decline to kick in. A player's career tends to dip a few years after they hit 30, and there's no reason why Fabregas should suffer before that time.
That will bring his stay in west London up to seven years if Chelsea opt to keep him beyond his 33rd birthday.
And they should.
Fabregas is a rare gem in the modern game. He's had his struggles with form at Chelsea this season, but few midfielders offer what he does when Fabregas is in peak form.
We need only observe Chelsea's last few outings to understand that.
Fabregas didn't grab the headlines in the recent 3-0 victory over Crystal Palace, yet what we saw on a soaking-wet afternoon in south London was a reminder of the talent that oozes through him.
As John Obi Mikel marshaled the midfield, Fabregas was given license to commit damage in the final third of the pitch. Which he did.
It was Fabregas' delightful through ball that put Chelsea in control of that game. He teased Damien Delaney with a perfectly weighted pass for Diego Costa, who squared to Oscar for Chelsea's opener.
That Fabregas executed the pass so expertly in such difficult conditions made it all the more impressive.
It was a throwback to last season, when few teams could live with Fabregas' threat, when he sailed free in the assists rankings with the presence of a man who seemed without peers.
The Spaniard was signed with a view to transforming the way Chelsea play football, which he did for a time. That's a vital thing to consider here as the search for answers surrounding Chelsea's slump has meant panic has ensued.
The reaction has been the usual in such circumstances: that something must change. That's led to transfer rumours surrounding a group of Chelsea stars, with Fabregas himself linked with Inter Milan and Juventus only last month, per Corriere dello Sport (h/t MailOnline's Daniel Prescott).
Part of the theory is right: Change has been needed at Stamford Bridge. It's the focus of that change that has been the problem.
For Chelsea to get back to performing anything like the team we saw in 2014/15, wholesale changes of the personnel are not in order. It's the way the current crop are utilised.
Fabregas is 18 months into his Chelsea career, and the feeling is that he's reached a crossroads that will determine how much longer he remains.
Chelsea have two options: Do the club consider the glass half-empty or half-full?
It's simple logic, yet effective. And the view must be that the proverbial glass is still filling up.
It would be folly to forget about the past six months that Fabregas has endured. Rather than casting him to one side, ripping up the plans to start again with another creative midfielder, Chelsea need to identify why he hasn't scaled the heights we were expecting.
It's only by addressing those issues that Fabregas can be consistent once more. That means finding the best system for these players and identifying Fabregas' best position in midfield.
After all, it's for that reason that managers are paid the money they are. It's why Jose Mourinho was sacked last month, as ultimately the club had lost faith in his ability to get Chelsea playing winning football again. The club no longer believed he could get the best out of his players.
Despite Chelsea's torrid campaign, it was still a surprise when Mourinho departed under such a cloud. He's Jose Mourinho, and that reputation precedes him.
Fabregas' should, too.
Roman Abramovich's decision ahead of Christmas was a vote of confidence in his players. Indeed, even when the owner was giving Mourinho his backing in October, he wasn't forgetting his players, either.
Chelsea's statement outlining their confidence in Mourinho after the crushing 3-1 defeat to Southampton was laced with undertones of how great these Chelsea players are viewed inside the halls of Stamford Bridge.
"We have the right manager to turn this season around and he has the squad with which to do it," the 57-word statement read.
Chelsea have since turned their back on the manager, but not the players. Even when Mourinho was sacked, the club stressed their belief in the squad. There was no palpable discord between owner and players at least.
If Mourinho wasn't the right manager to get Chelsea playing winning football, Fabregas most certainly is the right player.
It goes back to why he was signed. When Chelsea looked to replace Frank Lampard, they opted not to go down the like-for-like route. They didn't crave a box-to-box juggernaut like Lampard had proved to be.
The club wanted someone a little smoother around the edges, a player who could introduce the flowing spectacle Abramovich has long craved. Fabregas was identified as being capable of doing that, but he needs more than 18 months to change the culture of a football club.
Chelsea's transition on the pitch continues, and they need Fabregas to take it in the right direction. In five years' time, the landscape will look much different.