The Blues' captain has been in excellent form throughout 2013-14 and remains as inspirational as ever at the back for the club for which he has made over 600 appearances—a milestone he recently celebrated.
And it's the Mourinho factor that has made a considerable impact these past few months, seeing Terry return to his best. It's a fact not lost on the 33-year-old, either.
"When Jose came in, after the first week he said, 'For me, nothing has changed. You’re still top, you can still work and play at the top,'" explains Terry.
"He showed faith in me, and to get that arm around you is something everyone needs, even if you are one of the more experienced players in the team.
"At the time the manager spoke about it, I think I needed it and, when I got that from him, it not only made me feel 10ft tall, but it made me want to work even harder for the man in charge. It makes you go to that extra level—and I would give everything for the manager."
And give everything Terry has, leading from the front this term in much the same way he has throughout a career that has seen him lift every major honor in English football.
Terry has captained Chelsea to three Premier League titles, four FA Cups and the League Cup twice and also played a vital role in the club's journey to lifting the Champions League in 2012.
He isn't done there, though. Terry is hungry for more success at Chelsea and feels the current squad is capable of emulating the success of yesteryear.
“It is important that we kick on now, because everybody feels we have another gear to go to," he continues.
"I feel as though we have played well in spells [this season], but we have certainly got another level that we can go to and, if we do that, hopefully we can start to pull away from teams.”
With just two points separating the Blues and Premier League leaders Arsenal, it's certainly tight at the top right now. But with Terry looking as good as ever, there's no doubting the Blues are well positioned for a sustained title assault in the second half of the season.
Should that happen, it could very well be more than personal career milestones "JT" is celebrating come May.
*John Terry was talking to the official Chelsea magazine. The latest edition of Chelsea magazine will be available to download on your tablet from Jan. 13 at www.chelseafc.com/mobile
Garry Hayes is Bleacher Report's lead Chelsea correspondent and will be following the club from a London base throughout the 2013-14 season. Follow him on Twitter here @garryhayes