NEWTOWN SQUARE, — Keegan Bradley had bottomed out, crashing from the high of winning the PGA Championship to tumbling out of the 100 in the world. His chances to represent U.S. teams in international play had dried up, his preferred putting method was banned, and the confidence that once put him on the cusp of greatness was shot.

“It’s scary when I look back, because I didn’t know I needed this much improvement,” Bradley said.

He was like a scientist in the lab, changing his swing, his putting stroke, his fundamentals — investing in the work needed to get to where he was Monday on soggy Aronimink: going head-to-head in a sudden-death playoff against the new No. 1 player in the world, Justin Rose.

For a player who had to reinvent his game, the clutch moment didn’t seem so scary.

Bradley topped Rose with a par on the first playoff hole to win the rain-plagued BMW Championship for his first PGA Tour victory in six years.

Bradley’s fourth career win meant a bit more than the others — yes, even the major he won in 2011 — because he held more than a trophy and a $1.62 million check. He also got to give his young son Logan a victory toss in the air on the 18th green for the first time. Bradley, who shot a final round 6-under 64 to finish at 20-under 260, thrust his arms toward the gray sky and drizzle in celebration and waved his family toward him.

“I’ve won before, and I win and I finish, and I go home, just me,” Bradley said. “Now, I get to go back and we get to have fun and enjoy it together.”

Rose left Aronimink with a new reality as well. Though he was runner-up at the FedEx Cup playoff event, he didn’t come up short in the world ranking. Rose moved No. 1 in the world ahead of Dustin Johnson and became the 22nd player to reach the top spot since the ranking began in 1986.