The Grand National takes place at Aintree this afternoon, with one of racing's most extraordinary underdog stories set to unfold on the famous course.Twig, a bay gelding purchased for a mere 100, has the opportunity to secure a 1million windfall for his owners if he triumphs in the world's most celebrated steeplechase.The 11-year-old outsider, currently priced at 40-1, would effectively double the standard winner's purse thanks to a special offer from bookmaker William Hill after claiming victory in one of three qualifying trial races.Young jockey Beau Morgan, just 21 years old, will be in the saddle aboard the horse owned by his mother, Georgia.TRENDINGStoriesVideosYour SayBecause he won the Becher Chase, Twig is the only qualifier for the William Hill Half A Mill bonus, meaning If he wins the 2026 Grand National, his owner and trainer will receive the 500,000 first-prize money plus a 500,000 bonus.The Morgan family, who run a scaffolding firm near Bath, could scarcely have imagined reaching this moment when they acquired Twig half a decade ago.At the time of purchase, the horse had no jumping experience whatsoever, prompting the family to send him to local point-to-point trainer Matt Hampton for development.Over the summer months, Twig was turned out to pasture, where he built up considerable strength.Hampton's assessment of the horse's potential initially drew scepticism from the young jockey.Morgan recalled: "Matt said, 'This is a good horse' and I laughed and said we've heard it all before but to be fair he was right."Ben Pauling now trains Twig, and the horse arrives at today's race with genuine credentials after finishing 10th in last year's National.Morgan believes his mount has improved significantly since that previous attempt at the Aintree fences.LATEST SPORT NEWSAnimal rights group PETA release statement condemning Grand National after race-winning horse diesFootball manager, 49, dies after collapsing as Robert Lewandowski and Matty Cash pay tributeBritish golfer hints at 'gameplan' to end Masters hoodoo after suffering heartbreak last yearThe jockey said: "I'm sure he's in better form this time. His trainer says he has a sporting chance."The combination of youth and experience makes for an intriguing partnership.The 21-year-old rider is guiding an 11-year-old horse who has clearly matured into a serious contender for the sport's biggest prize.A total of 34 runners will contest this afternoon's feature race.It is set to begin at 4pm.Legendary Irish trainer Willie Mullins has entered eight horses in the field, including the bookmakers' favourite I Am Maximus.The JP McManus-owned runner claimed the National title in 2024 and is now attempting to achieve something no horse has managed since Red Rum's remarkable exploits in the 1970s.Should I Am Maximus prevail, he would become the first horse in nearly five decades to win the race, lose it the following year, and then reclaim the crown.Our Standards: The GB News Editorial Charter