Ruby Walsh has paid tribute to his late friend and fellow jockey Pat Smullen, whose death was announced on Tuesday.

Smullen (43) had been ill with pancreatic cancer since 2018.

"You kind of knew it was coming for the last while," Walsh told RTÉ Sport's Darren Frehill after the sad news emerged.

"He had ridden in Dundalk in mid March (two years ago), so when the opening day of the Flat came about, when Pat Smullen wasn’t there you were thinking, ‘Oh, there’s something amiss’. They were hoping it was gallstones but it was worse, it was pancreatic cancer.

"From that day forward, himself and (wife) Frances, what can you do but just get stuck in and figure out how you’re going to deal with it, cope with it and ultimately aim to make it better.

"But nobody was ever under the illusion other than it was going to be a very big battle. Pancreatic cancer is a very serious illness.

"From the word go, Pat took it on head on and was looking for a way to beat it, but he never wanted it described like that.

"If ever there was a horse named for Pat Smullen to ride it was (his 2000 Guineas winner) Refuse To Bend because he refused to bend as a jockey and he refused to bend all through his sickness as well."

"All through his career, you never ever saw a headline or story about Pat Smullen for the wrong reasons."

Smullen was crowned champion jockey on the Flat nine times. In eight of those years, Walsh was the champion over jumps. 

Walsh described the qualities that helped the Offaly man to forge such a successful career in the saddle. 

"You hear people described as ‘the ultimate professional’ and often wonder what that means," he said.

"He didn't have just one thing, he had a lot of everything to make him so good.

"Pat was incredibly dedicated. He had to do his homework and was always grateful for what he achieved.

"There were times he doubted himself too, but he had to overcome that. He was just a very good rider but also extremely punctual, hard-working, always spotlessly clean. He was a great communicator.

"He was a great judge of pace and always tactically in the right place, incredibly detailed and deep in everything he did, he put a lot of thought and effort into what made him a jockey."

Pat Smullen is interviewed after organising the 2019 Irish Champions Weekend Legends Race that ultimately raised over €2.6m for the cause

Walsh added that Smullen, who raised €2.6m for pancreatic cancer research before his death, had been a great support to his racing colleagues and had "led by example".

"He was a big character in the weighing room. He was a great man for the jockey's association, the Irish Injured Jockey’s fund.

"He was a good jockey for younger apprentices to talk to and he led by example.

"All through his career, you never ever saw a headline or story about Pat Smullen for the wrong reasons."

Cancer Trials Ireland paid tribute to Smullen and his fundraising impact in a letter to his family. 

"People diagnosed with pancreatic cancer in Ireland will feel the benefit of it for years, if not decades, to come," the letter read. 

"Clinical trials offer patients very real, tangible, important benefits – but they can also provide something as vital as it is intangible: Hope. That is Pat's real gift to the people who come after him, who are diagnosed with pancreatic cancer."

Dermot Weld highlighted Pat Smullen's loyalty and integrity in paying tribute to the man who was his stable jockey for the best part of 20 years.

The pair enjoyed untold success all over the world, winning the 2016 Derby at Epsom with Harzand, teaming up for several major Royal Ascot winners and having several fruitful trips to America.

"Pat Smullen was just a very, very special man, with regards to the sport of horse racing and indeed to me personally. He was unique," said Weld, speaking on Nick Luck’s Daily Podcast.

"In this day and age I would have to say his loyalty and his integrity stood out. He was my stable jockey for 20 years and was just the professionals’ professional.

"His detail and his determination were major factors, as was his bravery. He was a very principled man, he was a family man and his loyalty and integrity were an example to anybody within the sport.

"I only had two retained jockeys, Michael Kinane for about 13 years and Pat for about 20. We just built together, but he was simply an excellent jockey."

Highlighting some of their biggest successes together Weld went on: "You saw in England wonderful rides like on Rite Of Passage, two spectacular rides at Ascot.

"It is worth noting, from the limited chances he got at Ascot, rides like winning the Gold Cup on Rite Of Passage when he set the track record, Fascinating Rock in the Champion Stakes, Free Eagle in the Prince of Wales’s and on a horse called In Time’s Eye when he got the better of a great duel with Pat Eddery going way back to the early days (Wolferton, 2003).

"He won the English 2000 Guineas on Refuse To Bend and I think that typified the man. Right to the end when he was fighting pancreatic cancer he had this will to win, this belief, determination and he was able to impart that to the horses he rode.

"After he won the Epsom Derby (on Harzand in 2016) – and he so deserved to ride the winner of an Epsom Derby – the amount of public support, I can even use the word love at his achievement, was amazing. People not even connected to the sport sent him congratulations.

"It was the same right around the world. He won the Matriarch Stakes (Dress To Thrill 2002) one day for me and the respect the American jockeys had for him was very special. He was a leader in his own profession.

"He led by example, I think that is the best way I can describe him."

Kinane hailed a "top-class professional and top-class man" as he paid tribute to his long-time weighing-room colleague.

Smullen succeeded Kinane as stable jockey to Dermot Weld at Rosewell House on the Curragh in 1999 and enjoyed huge success in the role.

Smullen went on to become a multiple Classic winner, landing the Epsom Derby and Irish Derby (above) in 2016 aboard the Weld-trained Harzand.

"He was a gentleman. He came to Dermot's, things moved on and he took over my job and did a fantastic job for a long time," said Kinane.

"He was a top-class professional and a top-class man. We had some great tussles and we had some good times.

"Unfortunately, he couldn’t win his last battle, but he tried so hard."

One of Smullen’s keenest rivals throughout his career was Johnny Murtagh, who is now a successful trainer – and as recently as Saturday Smullen was still in touch with his old friend.

"The racing world mourns a true legend," said Murtagh.

"I had a big winner on Saturday (Champers Elysees in the Matron Stakes) and one of the first messages I had was from Pat saying 'well done, Johnny, brilliant win’ so he was showing class right up to the end.

"He set the standard in the weighing room in Ireland, everyone wanted to be like him – he was the champion jockey in Ireland in more ways than one.

"He leaves some legacy. We knew all about him in racing, but it wasn’t until he retired the wider community got to see what he was like, raising all that money for cancer research and pulling so many people together for his charity race last year.

"In and out of the saddle he was just a really great guy and my thoughts and now with Frances (wife) and the kids and his mam, all his family. It will be a tough few days, but we look on his life and career with very fond memories."

Six-time British champion jockey Kieren Fallon said: "He was a really nice guy, a very dedicated family man and what more can you say.

"I just want to remember him winning the Derby on Harzand at Epsom. Everyone was saying beforehand he is a lovely guy, but they were looking for something different – I said to one of the press boys 'he loves his tractors, so write about that'.

"I remember going in the weighing room the next day, we were together and he had that cheeky smile on his face shaking his head at me – I can still him now shaking his head and smiling at me!"

Having fought out plenty of finishes while rivals on track, it was the defeat Smullen inflicted on Fallon aboard North Light in the 2004 Irish Derby that he will best remember him for.

He added: "I was on North Light bidding to do the English-Irish Derby double and I thought I was a certainty. But Pat had other ideas and beat me on Grey Swallow. He was a very good judge and you don’t get to the top of your game without being a good judge.

"He wouldn’t give you an inch in a race, but that is what made him so good and a nine-times champion jockey. He was strong in the finish and he really did have all the attributes."

Fallon added of the disease that claimed Smullen's life: "He knew what he had was not easily fixed and whereas most of us, like myself, would have laid down feeling sorry, he got out there and really fought it.

"You would have not thought there was anything wrong with him that day at the Curragh for his charity race, as he was buzzing around as he wanted to be involved.

"He was so dedicated as he didn’t smoke and would only have the odd beer. I was hard on myself and I went (on riding) into my 50s, as did Lester Piggott, and I know he would have gone on for a lot longer if he could."

Frankie Dettori hailed Smullen as a "great man and a complete gentleman", having competed against him across the globe for more than two decades.

He said: "I’d travelled the world for 20 years with Pat and he was a great friend that fought until the end. It is always a shock when you get the news.

"I texted him about 10 days ago and he said he was not good and that he was back in hospital. It is such a shame as he leaves behind his wife and three children.

"He was a great man, not just with the horses, but with the way he conducted himself throughout the whole of this illness. He was a complete gentleman in every way."

Jamie Spencer was another to praise Smullen’s character both in and out of the saddle.

He said: "Our careers were parallel to each other and I’ve known him my whole professional career. I’m very saddened to hear of his passing and my thoughts go out to his family.

"In the saddle he was a great competitor. He was a very tough, but extremely fair rider and he would always do the right thing.

"He worked for Dermot Weld for two decades and that showed his loyalty. He was Mr Dependable off the track, as you saw what he did with his charity work while battling this illness.

"A lot of Flat racing involves travelling and you would have to spend a long time flying to hear anybody have a bad word to say about Pat."

Reigning British champion Oisin Murphy was another to hail Smullen’s talents in the saddle and commended his impeccable attitude towards up-and-coming riders.

He said: "Pat was an incredible rider and a brilliant tactician. He enjoyed so much success across the world, and he was such a popular rider all over the world.

"As a jockey he was a very good rider and a gentleman, while he was very good with young riders. I feel for his family at what is a tough time. He had so many friends and it was a pleasure to know him."

Newmarket trainer Hugo Palmer will always be grateful for his association with Smullen.

The pair teamed up for a number of big-race victories – most significantly with Covert Love in the Irish Oaks at the Curragh in 2015, as Smullen and the filly gave Palmer his first Classic success.

Palmer said: "I’m hugely saddened by the news that Pat has died. A finer jockey or finer man is impossible to imagine really.

"He was always a star to work with before and after a race, and was invariably brilliant in a race. He rode some great winners for me early on in my career.

"Short Squeeze and Gifted Master were two of the key ones, but his efforts aboard Covert Love in both the Irish Oaks, which was our first Classic, and in the Prix de l’Opera, which was a thrilling victory and an extraordinary ride, were things that I will remember forever.

"I’m just incredibly grateful not only for what Pat did for me and my career, but also to have known him. My heartfelt sympathy to his wife Frances and their three children."

Smullen also steered Harzand to victory in the Irish Derby for owner the Aga Khan. Pat Downes, general manager at the Aga Khan’s Irish studs, said: "It’s very sad news. We had some great days. Obviously Harzand’s two Derbys were the highlight.

"A great jockey, but also a great person and he battled hard for the last two years.

"It’s a terrible loss to his family – Frances, and (children) Hannah, Paddy and Sarah, and it’s just so sad, but I think in time we can all look back and feel lucky we have known him. He was a really great person."