John Hartson insists Jota owes Celtic and Ange Postecoglou for giving him the platform.
Now he believes a £6.5million capture on a permanent deal would be a return act of faith and loyalty on the part of the Portuguese ace.
And Hartson also reckons the champions-elect could treble their money in the future if they get a long-term agreement over the line now.
The on-loan Benfica attacker has the opportunity to stay in Glasgow in the long-term.
Celtic are keen to keep the 23-year-old and a deal is understood to be close.
Hartson knows Jota has done the business for the club since his arrival but he’s also aware of the opportunity which was afforded to him by the Hoops.
The new Parkhead hero has developed on a huge stage having come from the fringes of the set-up with the Lisbon giants.
Former Celtic striker Hartson said: “He’s been a great loan signing, hasn’t he? And it would be nice because I know there is not a lot of loyalty in football these days.
“Players come and go, players let contracts run down and these things happen.
“But Jota was very much an unknown quantity at Benfica a year ago now and Ange has given him a level and a platform to come and play at a global club like Celtic.
“To go and make a name for himself in Europe and a chance to play at a massive club with a huge expectation under pressure.
“Jota has been sensational at times. Yes, he’s had a couple of injuries. Yes, sometimes he didn’t hit heights of previous games or weeks but he’s done it in terms of his goals the past couple of weeks.
“If he has a choice of one or two clubs, I would like to think he won’t forget what Ange and the Celtic fans have done for him.
“As I say, there’s no loyalty in the game now. But I’d like to think that if he has the opportunity to sign, with what they have done for him as a young progressing footballer, he would stay.”
Asked if Celtic could double their money on Jota, Hartson said: “Absolutely. There’s no reason why they can’t. He’s young, he’ll get better. He’s not the same player that he was in Benfica’s B team and you get that.
“You get experience because you are playing in front of a crowd where you have to win.
“If you lose or draw in such a tight race, it’s not good enough. You have to win at Celtic and he has been part of a winning team.
“There’s no doubt if he keeps progressing and improving at the speed of knots he has done this season, they could double or treble their money.
“Everyone has money now. Southampton can pay £30m or £40m for a player. Championship clubs can pay.”
Hartson believes the draw of automatic entry to the group stage of the Champions League – as looks likely – is another huge carrot available to stars such as Jota and Cameron Carter-Vickers, who is also currently on loan from Spurs.
He added: “It’s absolutely massive. At the start of the season I can’t help but think, and this is not a dig at Rangers, that they thought the Champions League was theirs for the taking.
“They looked at it, considering the situation Celtic were in last summer, that even if they weren’t quite at the level they were under Steven Gerrard, they could still win the league. Even if they were at a level below.
“Look at the problems Celtic had. But for Celtic to overturn that and pip them... wow.
“We knew what the carrot was at the end of the season, the holy grail of the Champions League, the best platform a player can ever play at in his career apart from international football.
“All players want to play in the Champions League and you can’t help think what a difference that £40million could make, possibly more if they go through to the knockout stages, maybe go to £45-50million.
“Celtic run the house accordingly. They don’t overspend. They don’t push the boat out for many players unless they’re very special.
“Like Jota is, like Carter-Vickers. So this season, to have gone and got that carrot of £30-40m is fantastic.
“Champions League is very exciting, they can sell those three-game packages and everything else.
“Martin O’Neill always said, ‘If you do well for me then I’ll bang the chairman’s door down for you. I’ll be the first to get you a new deal.’
“So you’ve got to tie down those players who made a big difference. It has been a team and Ange is all about the team.
“Certainly Jota and Carter-Vickers would be two loan players, without anything else, I’d be looking to tie down on the back of how well they’ve done.
“I’m not just saying give these guys a contract because they’ve done it here and there. They’ve done it for a whole season and helped put Celtic on the brink of the title.”
● John Hartson was speaking at his Foundation’s annual golf day at Turnberry. John has raised more than £1million in the past decade for a variety of cancer causes.
