Enda Bolger led the tributes to JT McNamara after the former leading amateur rider died aged 41.
McNamara was paralysed following a fall at the Cheltenham Festival in 2013, when he fractured two vertebrae in his neck when Galaxy Rock came down at the first fence in the Fulke Walwyn Kim Muir Challenge Cup.
Renowned as one of the best amateur riders the sport has ever seen, McNamara partnered over 600 winners during his career, including four winners at the Cheltenham Festival aboard Rith Dubh (2002 National Hunt Chase), Spot Thedifference (2005 Cross Country Chase), Drombeag (2007 Foxhunter Chase) and Teaforthree (2012 National Hunt Chase).
McNamara enjoyed a special relationship with the Bolger-trained Spot Thedifference, steering the popular gelding to 11 of his 14 victories under Rules, including seven races at Cheltenham.
Bolger told Press Association Sport: "It's a sad day. He fought a great battle.
"He was one of those guys who only ever said three words but none would do. He was very unassuming and just a great person to have anything to do with.
"We had a lot of great days together and those are what I'll remember him for.
"He was an incredible horseman. I would say he was more of a horseman than a jockey."
Dr Adrian McGoldrick, senior medical officer for the Irish Turf Club, confirmed McNamara passed away peacefully during Monday night, just hours after the first day of the Galway Festival, another meeting where he enjoyed success.
McNamara is survived by his wife Caroline and children Dylan, Harry and Olivia.
"I remember him winning the big amateur riders' race on the Flat in Galway and that was a great feather in his cap as riding over fences was really his forte," said Bolger.
"He rode some very good horses in bumpers as well, including Like-A-Butterfly, who went on to win the Supreme Novices' Hurdle.
"He had an unbelievable record in Cheltenham. I think the Kim Muir was the only amateur race he didn't manage to win.
"He was a great guy and a great jockey and he'll be sorely missed.
"I know the last three years have been hell for him and his family and if there is a heaven, he'll be the first one in, that's for sure."
Spot Thedifference, Rith Dubh and Drombeag were among many horses McNamara steered to big-race success for JP McManus.
The leading owner's racing manager, Frank Berry, said: "It's so sad and all our thoughts go out to Caroline and the rest of the family.
"A nicer fellow you couldn't wish to meet. He was in great form up until maybe a week ago and he's definitely been a fighter. He fought a great fight.
"The boss and him and myself had so many great days together."
Legendary 20-times champion jockey Sir Tony McCoy recalled being in the weighing room at Cheltenham when news of McNamara's accident emerged.
"I remember looking over and seeing his clothes hanging up and thinking 'he'll never be back in here', and that's not something I'll ever forget," McCoy told RTE Radio.
"It's a very sad day for everyone in racing especially his wife Caroline, she's a very tough and amazing woman.
"He was a remarkable man. He was a little bit like me - he could be grumpy enough at times, but was very good humoured.
"He was fantastic, a brilliant rider. I said this morning that watching his ride on Rith Dubh at the Cheltenham Festival was as good as you'll ever see."