RIO DE JANEIRO -- This goodbye was golden.Michael Phelps put the United States ahead to stay on the butterfly leg of the 4x100 medley relay, his last race before retiring, and Nathan Adrian finished it off, giving Phelps, the most decorated athlete in Olympic history, his 23rd career gold medal.Two-time gold medalist Ryan Murphy put the Americans out front with a world-record split on the backstroke but Britain surged ahead on the breaststroke and Phelps dived into the pool in second place.On the return lap, Phelps powered through the water with his whirling butterfly stroke, surging ahead of James Guy to pass off a lead to the anchor Adrian.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.The victory came just minutes after the womens medley relay gave the United States its 1,000th Olympic gold medal in the history of the Summer Games.Also on Day 8 of the games, Usain Bolt thrilled the crowd at Olympic Stadium in his first appearance of the games and Rafael Nadals bid for an unprecedented second Olympic singles gold medal ended with a thrill-a-minute semifinal loss to Juan Martin del Potro.Monica Puig won Puerto Ricos first gold medal in any sport in Olympic history, upsetting Angelique Kerber in the womens tennis singles final. Puig is ranked 34th and is the first unseeded womens 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. She was trying to give Germany its first singles gold since Steffi Graf in 1988, but instead goes home with silver.While competitions wrapped up in swimming and rowing, theyre 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.Elaine Thompson won the womens 100-meter title in 10.71 seconds, ending fellow Jamaican Shelly-Ann Fraser-Pryces bid to win the event for a third straight Olympics. American Tori Bowie took silver.Phelps also said the London Games were his last four years ago only to change his mind.He insists he wont be coming out of retirement again for Tokyo in 2020.Im not going four more years and Im standing by that, he said. Ive been able to do everything Ive ever put my mind to in the sport and after 24 years in the sport, Im happy with how things finished.Other highlights from Day 8:GOLF GOLD : For all the talk about top players skipping Rio, the sport couldnt have asked for a better final round. Justin Rose of Britain is the third-round leader and will be trying to win golfs first gold medal in 112 years. Rose made two eagles in the opening five holes and shot a 6-under 65 to build a one-shot lead over British Open champion Henrik Stenson.SLUGGISH SPRINTER : Bolt did not disappoint the crowd, but he was displeased with himself. He was slow out of the blocks but once his tall majestic frame reached full flow, there was no stopping him. It wasnt the best start, it felt kind of sluggish, Bolt said, adding that he never has been a morning person and preparations for his noon race felt unusual.LONELY RUSSIAN : The IAAF has banned the only Russian in Olympic track and field from competition and she is appealing the ruling. A decision on Darya Klishinas petition is expected before the long jump competition begins Tuesday. The former European indoor champion was the only one of 68 Russians allowed to compete in track amid a doping scandal.GOODBYE GREEN : After blaming algae, heat and even the number of swimmers for the green water at Maria Lenk Aquatics Center, officials now say a contractor mistakenly dumped hydrogen peroxide into the pool, causing an adverse reaction with chlorine. So, theyre draining the larger pool to transfer nearly 1 million gallons from a nearby practice pool.PHOTO FINISH : After rowing for more than a mile, the gold medal came down to an inch. New Zealands Mahe Drysdale and Croatias Damir Martin crossed the finish line in the mens single sculls side by side, not knowing which one of them was the new Olympic champion. A photo analysis showed Drysdale won by a thumbs length.---AP Summer Games website: http://summergames.ap.org---Follow AP Sports Writer Arnie Melendrez Stapleton on Twitter: http://twitter.com/arniestapleton Fake Air Max Shoes . After Martin Skrtel put the Reds in front from close range at Stamford Bridge after only four minutes, Hazard hit back in the 17th with a superb strike. Etoo gave Jose Mourinhos team a decisive lead from Oscars back pass in the 34th. Fake Nike Air Max Online . Louis Rams wide receiver Stedman Bailey last Sunday. The fine is the fourth this season for Goldson. He was fined $30,000 for a hit on the New York Jets Jeff Cumberland in Week 1. http://www.fakeairmax.com/fake-air-max-200-cheap/ . -- Adam Snyder returned to the San Francisco 49ers this season because the offensive lineman thought it was his best opportunity to win a championship. Fake Air Max 2019 . Ancelotti says Ronaldo has recovered from a hamstring injury but "but he doesnt feel comfortable yet so we wont risk him." Madrid is third in the Spanish league, six points behind leader Barcelona, going into Saturdays game against Valladolid. Fake Air Max 1 Cheap . -- Matt Rupert scored once in regulation and again in the shootout as the London Knights extended their win streak to nine games by defeating the Owen Sound Attack 4-3 on Friday in Ontario Hockey League action. Niki Lauda says Nico Rosbergs late Q3 lap for second on the grid in Mexico was unbelievable given the really worrying position he found himself in during qualifyings early stages.?After struggling for pace and with tyre warm-up through the weekend, Rosberg could only manage fourth with the initial runs in Q3. Though the three drivers ahead of him did not improve at the end of the session, Rosberg did, shaving 0.3s off his time to jump ahead of the Red Bull drivers.That puts him second for the grand prix, alongside Lewis Hamilton, who he leads in the championship by 33 points and can beat to the title this weekend. Lauda thinks Rosbergs comfortable championship position would have been under threat without that late lap.Lewis was perfect, Lauda told Sky Sports F1. Nico was really worrying for his own sake because he would have starteed further back.dddddddddddd And if Hamilton wins, the championship goes further away. But then he got that lap in the end. It was unbelievable and he is on the front row.After qualifying Rosberg admitted he had taken longer than usual to get up to speed with tyre warm-up for his crucial laps. Lauda suggests he took a more conservative approach to qualifying than Hamilton.He could not get the car balance, its very simple. He did not get the right grip level into the tyres, which happened to his car.Lewis was more aggressive going out and with a little bit more temperature he got the car going quicker around the circuit. Nico could not get his tyres into the [right] tyre window but in the last lap he did. ' ' '