ELMONT, N.Y. – He had run nine times previously and had yet to win a graded stakes race nor a race on anything other than a synthetic surface. But on Saturday at Belmont Park, a colt named for Winston Churchill had his finest hour. Sir Winston, who had bypassed both the Kentucky Derby and the Preakness, jumped into the Triple Crown pool in time to score a 10-1 upset in the 151st Belmont Stakes before a crowd of 56,217. He held off favored Tacitus to prevail by one length in the 1 1/2-mile race, the difference likely being that Sir Winston was able to save ground on both turns while Tacitus took the overland route. Sir Winston gave trainer Mark Casse his second Triple Crown race win this season, following War of Will in the Preakness three weeks ago. War of Will was the only horse to run in all three legs of the Triple Crown, but the demanding schedule clearly caught up with him Saturday, as he finished ninth in the field of 10. “Maybe the mile and a half,” Casse said. “It’s a tough grind.” Joevia, the early pacesetter, held on for third, with Tax, who also had been prominent early, fourth. Master Fencer, the Japanese representative, finished well for fifth, then came, in order, Spinoff, Everfast, Intrepid Heart, War of Will, and Bourbon War. The win by Sir Winston means that – with Country House declared the Derby winner via disqualification – a different horse won all three legs of the Triple Crown this year. The last time that happened was 2017, a year in which Todd Pletcher, similar to Casse this year, won two Triple Crown races with two different horses. With so much chaos the first half of the year among the 3-year-old males, it sets up for a compelling second half of the year for the divisional title. The Belmont was the last of eight Grade 1 races run here on a gorgeous day Saturday, with a high temperature in the upper 70s and a nice breeze. Three of the Grade 1's went to trainer Chad Brown, two to trainer Steve Asmussen. Brown won the Just a Game with Rushing Fall, the Acorn with Guarana, and the Manhattan with Bricks and Mortar. Asmussen won the Met Mile with Mitole and the Ogden Phipps with Midnight Bisou. World of Trouble won the Jaipur, and Hog Creek Hustle the Woody Stephens. The Belmont belonged to Sir Winston ($22.40), the race’s fifth choice. He clearly has thrived since arriving at Belmont Park, where assistant Jamie Begg oversees the day-to-day operation for Casse’s far-flung stable. “Jamie has done a tremendous job with him,” Casse said. Sir Winston had finished fourth in the Withers, fifth in the Tampa Bay Derby – which was won by Tacitus – and seventh in the Blue Grass Stakes earlier this year, but stepped up his game last time out at Belmont when he finished strongly for second in the Peter Pan. Joel Rosario rode him for the first time in the Peter Pan, and opted for him in the Belmont over Everfast, who had finished second under Rosario in the Preakness. Rosario rode a brilliant race to take down his second Belmont. He hugged the fence around the first turn while toward the rear of the pack, then steadily advanced heading into the far turn while still on the rail. “He seemed like he didn’t mind the inside,” Rosario said. Rosario and Sir Winston crept closer on the far turn, then had to wait behind the tiring leaders, but found a seam near the quarter pole when Spinoff, who had been pressing the pace, weakened. Rosario quickly tipped Sir Winston to the three path to go around Joevia and Tax, then used his formidable strength to keep Sir Winston in front of Tacitus in the closing yards. Tacitus, favored at 9-5, was at least three paths wide on the first turn and four to five paths wide on the far turn. “It was a good trip. A little wide,” said Jose Ortiz, who rode Tacitus. “I think I was following the right horse, War of Will, the whole time  I tried to drop in on the first turn, but Johnny was already there,” he said, referring to John Velazquez, who rode Intrepid Heart. “I couldn’t do anything. I tried to save as much ground as I could,” Ortiz added. “Unfortunately, War of Will was a little bit flat on the second turn because I think if he had a little more horse he would have kept everyone else in, and I would have won. He gave me a good run.  I have no complaints.” Sir Winston covered 1 1/2 miles on the fast main track in 2:28.30. All the early fractions – 23.92 seconds for the quarter, 48.79 for the half, 1:13.54 for six furlongs, 1:38.27 for a mile, and 2:02.72 for 1 1/4 miles – belonged to Joevia. Casse was trying to watch both his runners during the race, but near the quarter knew he was down to one chance. “I could tell where War of Will was and could tell he was struggling,” Casse said. “Joel had ducked inside and to be honest I started hollering for Sir Winston at that point.” Sir Winston, a colt by Awesome Again, was bred and is owned by Tracy Farmer. He earned $800,000 Saturday from the overall purse of $1.5 million; he had earned $161,733 in his career going into the Belmont. Casse said Farmer had been ill this week, and though he was feeling better Saturday, “he wasn’t able to fly,” Casse said. “Just a shame,” he said. Sir Winston is not an imposing individual, and early in his career he showed little. “He’s an amazing little horse,” Casse said. “At this time last year if you had asked me to rank our top 20 2-year-olds, I would have ranked him 16th or 17th.” Sir Winston beat one horse in a dirt sprint at Churchill Downs to start his career 51 weeks ago, then beat one horse in a turf route at Saratoga. He began his ascension when subsequently sent to Woodbine, where on that track’s synthetic surface he won twice in three starts to complete his 2018 campaign. He was 0 for 4 this year going into the Belmont. But his connections kept marching forward. They never gave in. – additional reporting by Mike Welsch