Fletcher reunited with Bannan, his Scotland international teammate, at the end of his Sunderland contract in 2016.
But were it not for the Sheffield Wednesday midfielder's intervention - during an arduous drive from Glasgow to Norfolk - the 32-year-old is likely to have signed for Norwich instead.
Asked about his time at Wednesday, Fletcher replied: "It’s brilliant, mate.
"It was Baz who got me to sign. I was going down to talk with Norwich. Alex Neil was the manager - he’s probably still not happy with me, I don’t think.
"I was driving down and my agent had called me on the way down saying, listen, Sheffield Wednesday are keen. I was looking at the sat-nav thinking, there’s still six hours left from Glasgow to Norwich - still a long way to go. I was half-way, I was thinking, Sheffield’s just there, do you know what I mean?
"I texted him and said, what’s Wednesday like? He said, brilliant. I said, they want me to go speak to them. He said, you need to come. And I was like, right - sat-nav, changing it. I went in and signed that night.
"I had to tell Alex Neil, aye. He wasn’t happy. I can’t even say (what he said) on camera! Nah, it wasn’t too bad, just, OK. That’s even worse, isn’t it?"
Fletcher and Bannan have struck up a successful on-field partnership Sheffield Wednesday, and remain good friends away from the pitch, too.
The pair, who are known Celtic supporters, were recently revealed to have undergone hair transplants at the same Manchester-based clinic.
Post surgery thoughts from the boys this week. Looking forward to taking them through their aftercare and to see the results ahead @bazzabannan25 @DrMateeOfficial #fue #hairtransplant #kslclinics #kent #manchester pic.twitter.com/KYnynuQt2t— KSL Clinics | Hair Transplant Experts (@KSL_Clinics) May 8, 2019
They each hit double figures for combined goals and assists as Sheffield Wednesday finished 12th in the Championship this past campaign.
How good a signing has Fletcher been for Sheffield Wednesday?
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