Roger Federer and Serena Williams have pulled out of this seasons International Premier Tennis League (IPTL). The multiple Grand Slam champions were due to play in the final leg of this years event in Hyderabad from December 9 to 11. Federer was to play for the Indian Aces while Williams was to appear for the Singapore Slammers.We have had challenges this year, and we were hoping to get past them, Mahesh Bhupathi, founder and managing director of IPTL, said in a statement. With the current economic climate in India and the uncertainty of spending money, I reached out to both Roger and Serena to explain the situation. They have been both been very supportive of the IPTL the first two seasons and we look forward to bring them in future years.The withdrawal of Federer and Williams robs the tournament of its sheen. It had already been reduced to a three-city affair from the five cities that had featured on the calendar in the previous two years. There had been plenty of excitement surrounding the appearance of Federer and Williams, especially since both havent played competitively for a few months now. Federer has been out since July following knee surgery while Williams last played at the US Open, following which she has stayed away from the circuit with a shoulder injury. She was scheduled to appear in the Singapore leg starting today.The New York Times quoted Federers agent Tony Godsick saying his withdrawal was due to some problems and uncertainties surrounding the IPTL. He added that Federer hopes to play in future years if the IPTL continues. Though the organisers werent available for further comment, there has been speculation of the IPTL batting financial concerns. The significant reduction in the field along with a number of high-profile players being unavailable this year has led to speculation about the future of the event itself. In previous years, besides Federer and Williams, the likes of Andy Murray, Novak Djokovic and Rafael Nadal have played in the IPTL.ESPN learns that ticket sales in Hyderabad for the upcoming weekend have been slow as well, though that may be because of the cash crunch resulting from the governments decision to demonetize high-value currency notes. With world number 5 Kei Nishikori also ending his commitments for the year by appearing in the Tokyo last weekend, the highest ranking mens singles player left in the tournament is world number 10 Tomas Berdych of the UAE Royals. Cheap Old Skool China . DAmigo scored twice in regulation and added the shootout winner as the Toronto Marlies edged the San Antonio Rampage 5-4 in American Hockey League action. Wholesale Old Skool . The visitors took a deserved lead in the 16th minute with midfielder Yohan Cabaye curling the ball beyond Adrian from inside the penalty area. http://www.cheapoldskoolchina.com/ . LOUIS -- St. Cheap Old Skool Wholesale . -- The goal posts lying flat on the field, Arizonas fans lingered on the field, congregating around the locker room entrance nearly 30 minutes after rushing out of the stands. Cheap Old Skool From China . That left plenty of energy for pitching books and swatting away free agency questions. Anthony had 24 points and nine rebounds, and the Knicks avenged an embarrassing home loss with a rout of their own, beating the Boston Celtics 114-88 on Wednesday night for their third straight victory. NEW YORK -- The U.S. Open used its new, $150 million retractable roof atop Arthur Ashe Stadium during a match for the first time Wednesday night.The cover took about 5 minutes to close at 3-all in the second set of 14-time major champion Rafael Nadals second-round match against Andreas Seppi.After dealing with rain delays and postponed finals for years, the U.S. Tennis Association finally built a movable roof over its main stadium. It was available for this years tournament, which started Monday, but the first two days were dry.A light rain began to fall while Nadal and Seppi were playing. Tournament referee Brian Earley was monitoring the weather from off to the side of the playing surface and eventually walked over to chair umpire Cedric Mourier and the two players to let them know he wanted to shut the roof.This might take very few minutes, Mourier announced to the spectators. Thank you very much for your patience.Some fans applauded. Others pulled out their cell phones to shoot phhotos of the structure as it moved.dddddddddddd Even Nadal took a glance overhead to sneak a peek.In an interview with ESPN during its broadcast of the match, tournament director David Brewer said: This is why we built the roof in the first place.Asked what he thought of how things went Wednesday, he replied: Pretty sweet from my point of view.The USTA has said that, based on pre-tournament testing, the expectation is there will be little difference in playing conditions whether the roof is open or closed.The only use of the roof until Nadals match came when it was shut at the start of the tournaments opening ceremony Monday night, then opened while Phil Collins sang In the Air Tonight.The U.S. Open mens final was postponed in five consecutive years because of wet weather from 2008-12.---Follow Howard Fendrich on Twitter at http://twitter.com/HowardFendrich ' ' '