What you need to know:
- Barshim, 30, who holds the world title as well as joint Olympic gold, was sat alongside Tamberi as he made the statement on the extraordinary events of August 1 last year.
- Both cleared 2.37 metres and with neither able to make 2.39m, track officials offered a jump-off but Barshim famously asked: "Can we have two golds?"
Gianmarco Tamberi and Mutaz Essa Barshim, who provided one of the emotional peaks of the Tokyo Olympics by sharing the high jump gold medal, will not repeat the gesture if they are tied again.
"We already talked about it, it is not going to happen again," Italian Tamberi said ahead of his first clash with his Qatari friend since the Olympics at the Doha Diamond League meeting on Friday.
Barshim, 30, who holds the world title as well as joint Olympic gold, was sat alongside Tamberi as he made the statement on the extraordinary events of August 1 last year.
Both cleared 2.37 metres and with neither able to make 2.39m, track officials offered a jump-off but Barshim famously asked: "Can we have two golds?"
It was the latest episode in their unlikely rivalry-friendship that he has seen them console each other when each had a career-threatening ankle ligament injury.
But with a world championships looming this year, both know that sentiment has to be put to one side.
If they were tied again, "we will look at each other, we will say OK let's go" to the jump off, declared Tamberi at a press conference Thursday.
"For myself, I will never go back in the past and change what we have done. We will forever remember as brothers ... friends.
"We both won because we both deserved that gold medal. When they ask us will you share again we say 'no' because we have done it once.
"But it does not mean we are not proud of it. I will never change the past even if you paid me or guaranteed me that I will be the one who wins that gold medal, I will share with him because I know he deserves, I know I deserve."
Tamberi wants to add a world title to his Olympic gold. Barshim wants to establish his name among athletics greats by becoming the first to win three straight high jump titles at the world championships in Eugene in July.
The Qatari hero said it had already been "amazing" to be the first to defend the world title in Doha in 2019.
"Now I am trying to find some goal, some target to motivate myself and maybe it is even better to be the only one that did it three times so that keeps me going. It is not easy to find motivation after such a big year, such a big success."
Their competition will be a highlight of the opening Diamond League meeting of the year.
Swedish pole vaulter Armand Duplantis will be aiming for a new world record having set his latest best of 6.20m at the world indoor championships in Belgrade in March. No-one has cleared 6.0 metres at Doha's outdoor track.
But he is also aiming for a first world title to add to his Olympic gold and so has lined up a five meetings before Eugene.
"It comes down to these really tiny margins so I'm just trying to get everything in the right place for when it comes to competing in the world championships to make sure that, when the bar is at that gold medal height, I'm on the right pole, right grip, right run."
In the men's 200 metres, Olympic champion Andre De Grasse of Canada will compete against American world title holder Noah Lyles.