OWINGS MILLS, Md. — Patrick Cantlay, a creative if stoic player, was asked on Saturday night to look forward to Sunday’s final round of the BMW Championship when he would be paired with Bryson DeChambeau, the tinkering and volatile former college physics major.The golfers would begin the day tied for the lead.“Artist versus scientist?” a reporter inquired.Cantlay smiled and answered: “You should be able to decide.”The pair dueled across more than six entertaining hours and 24 holes on Sunday, with Cantlay typically imaginative and quietly effective while DeChambeau’s swashbuckling style and mighty swipes at the ball overpowered the Caves Valley Golf Club outside Baltimore.But what transpired was more than a riveting contrast of styles. It became a test of will between promising 20-something golfers, young faces who are at the advent of the sport’s transition from the Tiger Woods era. It was a show and the cast of characters were all new.The tournament lead shifted several times, but neither golfer was able to escape his final pairing shadow. Raucous whoops and hollers greeted DeChambeau’s gargantuan drives, animated fist pumps and purposeful, marching strides. Respectful, if restrained, applause followed Cantlay’s steady, emotionless efforts and languid pace of play.It could have been golf’s version of the folk tale, “The Tortoise and the Hare.”Finally, on the sixth playoff hole, Cantlay, 29, sank an 18-foot uphill birdie putt and offered a subtle, most rare grin. DeChambeau, 27, could not match his opponent’s resolve as the sun began to set in Maryland, missing a nine-foot putt that would have extended the contest.It was Cantlay’s fifth victory on the PGA Tour and his second this year. The win puts him in a commanding position entering the season-ending Tour Championship, which is the last of the three stages of the FedEx Cup playoffs, with a $15 million prize for the champion.“It was an unbelievable atmosphere all day and I just tried to stay in my own little world,” Cantlay, who is ranked 10th in the men’s world golf rankings, said afterward. “The fans were so energized and into every shot. It’s really nice to have them back.”DeChambeau has been a crowd favorite since he gained 40 pounds last year and began launching awe-inspiring 370-yard drives. He has learned to stoke and play to his galleries and for most of Sunday’s round he was the people’s choice. But in time, the understated Cantlay nurtured a following of his own.Perhaps impassive is the new cool. Or as Cantlay noted, toward the end of Sunday’s round fans had begun chanting a new nickname at him: “Patty-Ice.”“I’ve never heard that,” Cantlay said.DeChambeau, as he has for the last several weeks, did not meet with reporters after Sunday’s round. But he did speak to Cantlay about his golf course etiquette when the two were on the 14th hole. In an unusual exchange, DeChambeau asked Cantlay to stop walking as DeChambeau was preparing for one of his shots.“He just wanted me to stop walking,” Cantlay explained. “The rules officials had told us to speed things up. But it was no big deal. Those things kind of happen out here from time to time.”When the contest moved into a playoff after 18 holes left Cantlay and DeChambeau tied, the drama only intensified. Cantlay nearly sank a crafty pitch attempt on the first playoff hole but settled for par, a result matched by DeChambeau when his lengthy birdie putt slid just past the cup. On the next hole, Cantlay left his approach shot to the par-4 18th green more than 50 feet short of the hole but artfully two-putted for par. DeChambeau had a six-foot birdie putt to end the tournament, but as he did several times earlier in the round, he yanked his golf ball left of the hole.On the fourth playoff hole, DeChambeau made a startling error when he splashed a tee shot into a creek to the right of the 18th hole. But he overcame the misplay and a par was good enough to send the competition to a fifth playoff hole, which also ended in matching pars.The closing moments of the initial 18-hole round also did not lack for intensity. Indeed, Cantlay appeared to have squandered his chances on the 16th hole when a substandard chip shot led to a par. DeChambeau moved ahead by a stroke when he birdied the hole. Then, Cantlay’s tee shot on the 186-yard 17th hole landed 10 yards short of the green and bounced sideways into a pond before he finished with a bogey.But DeChambeau, who struggled with his chipping throughout the tournament, flubbed a pitch from the rough just inches from the green and made bogey, a score Cantlay matched. At the par-4 18th hole, each player reached the green in two but Cantlay rolled in his curving, right-to-left, 22-foot birdie putt while DeChambeau badly pulled his 15-foot birdie putt to the left and made a par.When his victory was secured Sunday evening, a smiling and even giggling Cantlay remained on the green and saluted the spectators by doffing his cap and waving it at the grandstand. He repeatedly said, “Thank you,” although his words were drowned out by applause.