NEW YORK -- Juan Martin del Potro is the lowest-ranked man to reach the U.S. Open quarterfinals since Jimmy Connors in 1991, and it turns out a 27-year-old Argentine can share much in common with a 39-year-old American.At its root, the story captivating fans at Flushing Meadows is the same: the former champion making an unlikely run to reclaim past glory.In del Potros case, his body has betrayed him through injuries, not age -- multiple left wrist surgeries that kept him from the majors for 2+ years. The only thing missing from his tale so far at this tournament is a marathon match.Mondays victory was particularly brief after eighth-seeded Dominic Thiem retired in the second set because of a bum knee. For once, an injury was aiding del Potro, not hindering him.Still tired after the stunning run to an Olympic silver medal that announced him as a contender again, he got a huge break in spending only 72 minutes on court. Del Potro has played just 10-plus sets through four rounds and got in some extra hitting after Mondays match abruptly ended.Thiem took a medical timeout to have trainers look at his right knee after the second sets fifth game. He returned to the court for one point before deciding he couldnt go on.Del Potro had won the first set 6-3 and was up a break in the second. He had trainers massage his right shoulder on a few occasions but looked fine after coming back from down an early break.Thiem said his knee started hurting three days earlier, and he speculated it was the indirect result of blisters on his feet -- he needed to alter his gait to compensate. Late in the first set Monday, it started getting worse. He didnt want to take any risks with a knee injury and planned to get an MRI.I couldnt bend it too much the last three days, he said. So I was all the time a little bit handicapped.Thiem, who turned 23 on Saturday, has had a breakthrough year, reaching the French Open semifinals and cracking the top 10. But all those victories came with a cost -- a tour-high 69 matches, and the long season had started to wear on his body. On top of that, he had played 12 sets through three rounds at the U.S. Open.I never expected to play that many matches, of course, this year, he said. For sure next year Im going to change it up a little bit.Del Potros quarterfinal opponent will be third-seeded Stan Wawrinka, who has already made a cameo in this saga. In del Potros first Grand Slam back, his second-round upset of Wawrinka at Wimbledon initially hinted at a return to the top of the sport.He will be the favorite to win in that match, del Potro insisted, before adding: But anything can happen in this event for me. I got the power from the crowd in every match.In Wawrinkas victory Monday, the two-time major champ blew a lead, smashed a racket and eventually pulled it out in four sets against 63rd-ranked Illya Marchenko, who was playing in his first Grand Slam round of 16. The other mens quarterfinal Wednesday will be second-seeded Andy Murray against No. 6 Kei Nishikori after both posted commanding straight-set wins.On the 25th anniversary of the 174th-ranked Connors rousing run to the semis, del Potro, at No. 142 in the world, is a win away from that stage. Hes already in his first major quarterfinal since 2013 Wimbledon.Del Potro recalled in his on-court interview after Mondays match how sad he was to watch the U.S. Open on TV, stuck at home the last two years.I didnt expect to be in quarters in my second Grand Slam after my comeback, he said later. Im playing good tennis. My level is growing up every day.Somebody noted that at the 2009 U.S. Open, which ended with a victory over Roger Federer in the final, he beat an Argentine, an Austrian and a Spaniard along the way -- just as hes done this year.Del Potro burst into laughter and replied: I only remember the finals against Roger, and hes not here. But its a good point. Yeezy From China . Tracey comes to the Blue Bombers after spending over a decade with Queens University. Most recently he was the schools assistant football coach. China Shoes Store . -- Catcher Brett Hayes has agreed to a $630,000, one-year contract with the Kansas City Royals, avoiding salary arbitration. https://www.chinashoes.us/ . Anthony Davis had 31 points and 17 rebounds in his seventh straight game with more than 20 points, but that was only enough to keep the Pelicans competitive into the final minutes. Andrew Bogut had 10 points and 15 rebounds for Golden State, which rebounded from a loss a night earlier in Oklahoma City and snapped a two-game skid. China Shoes . President of baseball operations Larry Beinfest was fired Friday after 12 years with the Marlins. The move came as the team neared the end of its third consecutive last-place season in the NL East. China Shoes Cheap . The No. 1-ranked Nadal tweaked his back warming up for the Australian Open final, which he lost almost four weeks ago in a major upset against Stanislas Wawrinka. His first stop after the layoff is the clay in Rio as he tests the back and tries to stay healthy for the French Open in three months. RIO DE JANEIRO -- Amnat Ruenroeng speaks openly, even eagerly, about his years in a Thai prison.His path out of poverty, crime and drug addiction began in a cell. He wants it to end in an Olympic ring with a medal around his neck, and he was willing to return from the pro ranks to try for that storybook ending again.There are some good parts of being in prison, Ruenroeng said through a translator. You get discipline. You learn how to know whats right and whats wrong. In the prison, they provide education, and they have boxing, football and martial arts. Im good at boxing.Eight years after Ruenroeng fell just short of a medal in Beijing, the 36-year-old former IBF flyweight champion got his second Olympics off to another winning start Sunday night.Fighting 11 kilograms above his professional weight after qualifying for the games just one month earlier, he still beat Argentinas Ignacio Perrin by decision.I felt good, but I must do better because this is my chance, he said.When AIBA invited professional boxers to attempt to qualify for the Rio de Janeiro Games earlier this year, no big international names accepted the offer, and only three pros are in the Rio field. But Ruenroeng eagerly seized the chance just a few weeks after losing his professional title, and he earned qualification last month.He is hardly a man among boys in the amateur game, however: Ruenroeng decided to fight at the 60-kilogram lightweight limit, a whopping 11 kilograms above his flyweight professional limit. He was stopped during the qualifying tournament in Venezuela last month, and he will have to beat two more veteran Olympic-style fighters to get a medal in Rio.Its difficult, because my opponents have an advantage, Ruenroeng said. Theyre bigger, but I have the will.The risk was negligible to Ruenroeng, who still feels he owes a debt to boxing. He also shares many Thai athletes devotion to the King of Thailand, who pardoned him from a 15--year sentence after he showed boxing talent.dddddddddddd.Thats why I came here for a second time, to prove myself, he said. I have to find out whether I can get the Olympic medal or not.The second chapter of Ruenroengs life has been all about righting wrongs.A grade-school dropout, Ruenroeng said he went to jail three times and was serving a 15-year sentence for robbing a tourist when he first discovered his knack for boxing through a prison athletics program. He soon had a national title, a pardon and a purpose: To win internationally for Thailand, which has a decent history of boxing success.He earned a spot at the Beijing Olympics and won two fights, but fell one fight short of a medal in the light flyweight division. He lost a painful 5-2 decision to Mongolias Purevdorjin Serdamba, who went on to win silver.Ruenroeng didnt turn pro until 2012, but he had quick success. He won his title in January 2014 and defended it five times, even trouncing two-time Olympic gold medalist Zou Shiming last year.The amateur sport has changed since Ruenroeng and Zou left it. The fighters no longer wear headgear, and the Olympics are scored under a version of the 10-point professional standards instead of the punch-counting system used in Beijing.Ruenroeng didnt change much about his approach, sticking to the skills that had kept him unbeaten as a pro under Johnriel Casimero stopped him and took away his belt in May.Ruenroeng misses his wife and son back in Thailand, but he speaks to them daily. He sounds like the very definition of a rehabilitated prisoner when he looks back at the path behind him and the possibilities ahead.(Prison) made me know the importance of the family, of my friends, Ruenroeng said. It taught me that whatever I do, I have to have a conscience. I have to think before acting. ' ' '