A terminal cancer patient who conquered Mount Everest after being told he had only months to live has died.
Ian Toothill, 48, previously said he believed he was first cancer patient to scale the world's highest mountain.
The Sheffield Wednesday fan planted a flag of rivals Sheffield United - in a bid to boost donations to cancer charity Macmillan - when he reached the summit in June last year.
Friend Richard Barker described him as "a proper Sheffield lad".
"I remember talking to him before the climb, and we were talking buckets lists... and he said 'I want to climb Everest'."
Mr Barker said: "Don't you remember you've got cancer?".
But then looked at his friend and said he thought "he is going to do it".
Announcing the news on Twitter on Thursday, Mr Barker thanked fans of both Sheffield football clubs for their support, prompting tributes from both sets of fans.
@L0RD_H @TWWcast it's with great sorrow that @IanToothill passed away today. Can you thank all your listeners, Sheffield Wednesday fans, Sheffield United fans, Sheffield United Fc and special thanks to Mr Mcabe and Dave Mcarthy at SUFC for their support, thanks you to you 2— Richard Barker (@rich_b123) January 18, 2018
One tribute read: "Simply a magnificent and inspirational human being - today we are all Sheffielders."
Fans also praised Mr Toothill for planting the "United flag" as a bet to boost his fundraising efforts.
Mr Toothill, who was originally from Sheffield, but moved to Willesden Green, London, was unmarried and had no children.
He previously said he had always planned to climb Everest but had been forced to bring it forward.
"Sometimes life changes, and you just have to get after it," he said.
He reached the top of the North Col route on 16 May and the summit of Everest on 5 June, despite being hampered by storms, and having had his tent destroyed.
He also suffered snow-blindness and a temporary loss of vision - on the way down.
However, Mr Toothill, who was a personal trainer, said after the climb: "I still had a great time. I got the full Everest experience."