The 23-year-old Jankovic, who was appearing in her first final in her 21st Grand Slam event, fought gamely to the end, extending points with her dogged defense. Her nerves, which were indiscernible at the start, surfaced in the 20th game, serving at 5-4, when she squandered four set points on her serve. “I gave her a lot of gifts when it was crucial,” Jankovic said, adding: “I had a lot of chances, so many set points, so many things to win that second set and go into a third. I let my opportunities go away.”

After breaking her with a forehand passing shot, Williams won 10 of the final 16 points to secure her ninth major singles championship. Williams converted her second match point with a backhand that fell as softly as a tissue, then dropped her racket and hopped up and down. When at last she made it to the net, she apologized to Jankovic for getting so excited