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Pancho Alvarino told The Associated Press the relationship between his TenisVal academy and doctor Luis Garcia del Moral "started approximately 14-15 years ago."
That overlaps with del Moral's work for the U.S. Postal Service cycling team. The USADA says del Moral helped to implement a "team-wide doping program" as a doctor for USPS from 1999-2003, when Armstrong won the first five of seven Tour de France titles now stripped from him for doping.
The USADA in July handed the doctor a lifetime sports ban. Del Moral criticized the agency's proceedings and said he never witnessed organized doping at USPS.
Replying by email to questions from the AP, Alvarino said "many of our players" consulted del Moral for preseason blood tests, strength tests and for injuries. TenisVal and del Moral's clinic are both in Valencia, on Spain's east coast.
He indicated the academy has now severed the link. "After Armstrong's news, no player from TenisVal has (had) contact or any kind of relationship with him," he wrote.
"If I had had the minimum evidence of Dr. Del Moral doping any player from the Academy, don't even hesitate I would have denounced the doctor, as well as the player," Alvarino, writing in English, told the AP.
Players used to pay the doctor's clinic directly, Alvarino said. He said del Moral never helped any tennis player with doping.
"Dr. Del Moral was the doctor who practiced blood tests ... and strength tests to the players of the Academy on pre-seasons, as well as injuries treatments," wrote Alvarino, a former player, and captain of Spain's first Fed Cup-winning team, in 1991.
"Dr. Del Moral has been always a very important personality in sports medicine in Valencia and he has worked with many sports people and sports teams from many countries, as everybody knows."
Sara Errani of Italy, the losing finalist in women's singles at the 2012 French Open, said in September that del Moral "was the best doctor in Valencia for everything, so I have been working with him, of course."
Errani added she would no longer consult him because "his name is not (a) good name."
Former top-ranked woman Dinara Safina of Russia also consulted del Moral when she was at TenisVal. Russian website Sport Express last month quoted Safina as saying del Moral "has the only real clinic in Valencia where athletes can undergo tests before the beginning of the season and at the end. And we underwent the tests in this clinic. We ran on the treadmill, they took blood samples from our ears, and so on."
"Del Moral gave us no advice whatsoever and did not handle our cases," Sport Express quoted Safina as saying. "I have nothing to be afraid of. I'm clean."
The manager of the International Tennis Federation's anti-doping program, Stuart Miller, said he investigated del Moral's work in tennis in the wake of the USADA's ban.
The ITF "interviewed Sara Errani, among others," Miller told the AP. Citing confidentiality requirements, he wouldn't say how many people were interviewed, name them, discuss the status of the investigation and its findings, or say if the ITF determined whether del Moral helped players to dope.
"We have done an investigation," Miller said. "It's been done to the best of our ability."
"If there's a case where somebody has breached the rules, it will be publicly reported. So you can draw what conclusions you like from that."
Alvarino said TenisVal coaches always accompanied players on visits to del Moral. "They never attended on their own," he said.
The academy didn't pay del Moral but "suggested (to) the players that, before each pre-season, they should have blood tests and strength tests in order to get information about their physical condition, so we could know the intensity or type of training we could apply to each player."
Del Moral has disputed the USADA's evidence against him.
In a statement posted last month on the website of the Valencia clinic where he works, he said: "During the years that I was with the medical team of U.S. Postal I never was witness to doping organized by the team, nor of course any that I (supposedly) facilitated or promoted."
"Beyond a doubt, I have not participated in any doping ring, nor has it been proven," the statement said.
In affidavits, former Armstrong teammates told the USADA that del Moral drew up doping plans, injected them and supplied them with the banned blood-boosting hormone EPO as well as testosterone, human growth hormone and cortisone, and helped extract and re-infuse blood for banned performance-enhancing transfusions.