In Olympics, a first for Puerto Rico and 23rd for Phelps

United States' Michael Phelps and Britain's James Guy compete in the men's 4 x 100-meter medley relay final during the swimming competitions at the 2016 Summer Olympics, Saturday, Aug. 13, 2016, in Rio de Janeiro, Brazil. (AP)

RIO DE JANEIRO (AP) — Michael Phelps claimed his 23rd gold medal. Puerto Rico won its first ever. And Jamaica got its first gold of the Rio Games with an emphatic win in the marquee Olympic sprinting event.

Phelps helped lift the 4×100 medley relay team to victory Saturday in what marked his last race before retiring, capping a night of extraordinary accomplishments in the 2016 Olympics.

Elaine Thompson of Jamaica won the women’s 100-meter title in 10.71 seconds, ending fellow Jamaican Shelly-Ann Fraser-Pryce’s bid to win the event for a third straight Olympics. She won the race in dominating, Usain Bolt-like fashion — and it may be a sign of things to come for Jamaica in the coming days.

Bolt thrilled the crowd at Olympic Stadium on Saturday in his first appearance of the games, and he will go for gold in the 100 meters Sunday.

Monica Puig won Puerto Rico’s first gold medal in any sport in Olympic history, upsetting Angelique Kerber in the women’s tennis singles final. Puig is ranked 34th and is the first unseeded women’s singles gold medalist since tennis returned to the Olympics in 1988.

Seeded second, Kerber won the Australian Open in January and was the runner-up at Wimbledon last month.

On the men’s side, Rafael Nadal was toppled by Juan Martin del Potro of Argentina, ending his bid for a second Olympic singles gold medal.

While competitions wrapped up in swimming and rowing, they’re just heating up in track and field, where Mo Farah of Britain recovered from a fall to defend his Olympic 10,000-meter title and American Jeff Henderson overtook Luvo Manyonga of South Africa on his last jump to win the long jump gold medal.

Phelps’ victory came just minutes after the women’s medley relay gave the United States its 1,000th Olympic gold medal in the history of the Summer Games.

If this was indeed the end, then Phelps went out in style, with 28 medals overall, having won five golds and a silver in Rio de Janeiro. He also said the London Games were his last four years ago only to change his mind.

He insists he won’t be coming out of retirement again for Tokyo in 2020.

“I’m not going four more years and I’m standing by that,” he said. “I’ve been able to do everything I’ve ever put my mind to in the sport and after 24 years in the sport, I’m happy with how things finished.