A win that proved he has reached a different dimension, a testament to his growth. Kei Nishikoris five-set victory over Andy Murray in the quarter-finals of this years US Open was one of the best of his career. Probably one of his biggest since reaching the final in New York in 2014.And it was impressive, coming over four hours and from two sets to one down. But was it, as Japanese tennis veteran Kimiko Date-Krumm suggested, a victory that proved the 26-year-old Nishikori has reached a different dimension? For many the jury is still out.Not that Nishikori has not been successful already. He has won 11 career titles, an Olympic bronze medal, reached the final of the US Open, made three Masters finals, and hit as high as No 4 in the world. But there has been a common theme that seems to have prevented any further progress: fatigue or injury.In the 2014 US Open final he was beaten in straight sets by Marin Cilic, saying afterwards that his body was heavy. After losing in the semi-finals in New York to Stan Wawrinka this year, he said: I was definitely tired, especially in the end. At Wimbledon he did not look fit from the outset against Cilic and eventually retired at 6-1 5-1 down. Nishikori beat Andy Murray at this years US Open There is no doubting Nishikoris talents, but his progression to the very top has been hampered by consistent injury issues. There is also a question of whether he can physically go the distance throughout the two weeks of a Grand Slam.In 2014, one of his coaches, Dante Bottini, said that part of Nishikoris problem with injuries was mental and he didnt really know how to deal with pain and injury.It was a clearly a priority for Nishikori and his team at the time.If I have one goal for next year that would be for Kei to go out there and play 95 percent of the year healthy, said Nishikoris coach Michael Chang in December 2014. To go through the year without having an injury or something happen that takes you out for two to three weeks at a time would be a huge accomplishment and that alone would take his tennis to the next level. Mark Petchey looks ahead to the ATP World Tour Finals Chang also said that he felt Nishikori had an opportunity to win a major on any surface.That challenge, though, has not materialised. While he has performed well at the US Open, he has never made it beyond the fourth round at Wimbledon, has only made one quarter-final at Roland Garros and never progressed beyond the last eight in Melbourne.So what does Nishikori need to do to make the next step up?Perhaps his injuries have just been bad luck. Perhaps he need to lighten his load in 2017 and the years ahead. One aspect that could really help him win a Slam would be his serve Michael Chang I have been playing a lot of matches this year, he said last week. Maybe thats why I have been hurting these couple months, not feeling 100 percent yet.At the moment his body seems as though sometimes it is his toughest opponent.But because of his style of play that might not change. Nishikori does not have a huge serve - of the eight players in London he has the fewest aces in 2016 - and rather he excels with his court coverage and brilliant backhand.But grinding out so many points appears to be taking its toll on the world No 5.Chang admitted earlier this year that one aspect that could really help him win a Slam would be his serve. Michael Chang started working with Nishikori ahead of the 2014 season He added: Its improved a lot over the past couple of years but it still needs to get better and more consistent.Nishikori mixed it up at the US Open by serving and volleying, using the tactic to great effect against Murray in the quarter-finals.Sky Sports pundit Mark Petchey said: Hes definitely trying to protect his serve a bit better this year against obviously great returners.But will that be enough for Nishikori to consistently compete with the best?Ahead of the ATP World Tour finals, he acknowledged: I have to do a little better in the big tournaments, especially the Grand Slams and all the ATP World Tour Masters 1000s.Physically, I got much stronger the last couple of years. I try to work hard every day, try to be confident in every match and enjoy my tennis. Its good motivation.Is motivation enough to see the Japanese make the next step? That remains to be seen.Check our game-by-game coverage from all group matches at the ATP World Tour Finals in London - including Andy Murray - on skysports.com/tennis, our app for mobile devices and iPad and our Twitter account @skysportstennis. Also See: Panel predictions Stan the danger man Murrays year in numbers Tour Finals at The O2 Youth Raiders Jerseys . -- Jimmie Johnson held off a teammate, passed a pair of Hall of Famers, and dominated once more at Dover. Raiders Jerseys From China . 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. http://www.cheapraidersjerseyschina.com/arden-key-jersey/ . -- Derrick Rose shook off poor shooting early to hit clutch shots late and Carlos Boozer had 20 points and 13 rebounds to lead the Chicago Bulls to a 104-95 preseason victory over the Oklahoma City Thunder on Wednesday night. Discount Raiders Jerseys . "Jeff is a hard worker who was an important special-teams contributor for us last season," said Stamps GM John Hufnagel. Cheap Raiders Jerseys . All of the scoring came in the final 20:04. Lucic scored on a power play at 15:46 of the third period, when he tipped a shot over Stars goalie Kari Lehtonen for a 3-1 lead. NEW ORLEANS -- Al-Farouq Aminu has agreed to a 1-year extension with the New Orleans Pelicans, a person familiar with the situation said. The person spoke to The Associated Press on condition of anonymity Saturday because NBA rules prevent the deal from becoming official until July 10. On his Twitter page, Aminu posted the message: "Excited to be back in NOLA." The extension was first reported by the Times-Picayune, which said the deal was for $3.7 million. The 6-foot-9 Aminu, heading into his fourth NBA season, started 71 games last year, playing mostly at small forward. He averaged career highs of 7.3 points and 7.7 rebounds per game, with season-highs of 20 rebounds against Dallas on April 17 and 18 points against Boston on Jan. 16. Aminu was drafted eighth overall out of Wake Forest in 2010 by the Los Angeles Clippers. He came to New Orleans as part of a 2011 trade that sent Chris Paul to the Clippers, and which also brought shooting guard Eric Gordon to the Pelicans, who were then called the Hornets. Aminus first chance to start regularly came last season, and coach Montty Williams spoke highly of Aminus rebounding and all-around athletic ability.dddddddddddd But Aminu was unable to demonstrate that he could provide consistent scoring from the wing position, and the Hornets went into this off-season with both Williams and general manager Dell Demps acknowledging that the club was looking to acquire another small forward. A recent trade reported by multiple outlets including AP will bring Tyreke Evans to New Orleans once its official should help the Pelicans in that area when matchups allow. However, the 6-6 Evans appears more suited to playing shooting guard and would likely have a height disadvantage if forced to play heavy minutes on the wing. Demps said during the NBA draft that he expected to be very active in free-agency. His next moves could include not only the acquisition of another wing player, but also a centre. Robin Lopez, who started at centre for New Orleans last season, was sent to Portland as part of the three-team deal involving Evans that was agreed upon on Thursday -- and also sent guard Greivis Vasquez to Sacramento. ' ' '