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The man behind a Florida clinic now under investigation by Major League Baseball for an alleged doping operation reportedly injected New York Yankees superstar Alex Rodriguez with performance-enhancing drugs.

Sources told ESPN’s “Outside the Lines” that Anthony Bosch would visit Rodriguez’s waterfront mansion in Miami every few weeks, including last spring when, according to a source, Bosch told associates he had been kicked out of the infuriated former MVP’s home after having trouble locating a vein. It’s unclear why Bosch would have been tapping a vein, however, since human growth hormone and steroids do not require intravenous injections, sources said.

“Tony said A-Rod was pissed at him,” a source said. “He said he was bleeding everywhere.”

Several sources who spoke on condition of anonymity told “Outside the Lines” that Bosch spoke openly about his relationship with Rodriguez, and two sources said documents they reviewed detailed the drug regimens and schedules Rodriguez received.

Procedures were different for other athletes being served by Bosch’s Biogenesis of America clinic in Coral Gables, according to the report. Those athletes, sources said, used couriers to transport the drug regimens Bosch provided.

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“Only Tony handled A-Rod,” one source said.

A spokesperson for Rodriguez denied the allegations on Friday.

Rodriguez was named in a bombshell report in the Miami New Times on Monday as one of several athletes listed in paperwork from Biogenesis.

Biogenesis, according to the weekly newspaper, was run by Bosch in a nondescript office park and is no longer listed as a business in its directory. The newspaper said it obtained records detailing purchases by Rodriguez and other notable players, including Toronto Blue Jays outfielder and 2012 All-Star game MVP Melky Cabrera, 2005 AL Cy Young winner Bartolo Colon and 2011 AL Championship Series MVP Nelson Cruz.

Other players whose names appeared in the records included Washington Nationals pitcher Gio Gonzalez and San Diego Padres catcher Yasmani Grandal. Gonzalez finished third in last year’s NL Cy Young Award voting.

The New Times posted copies of what it claimed were Bosch's handwritten records, which were obtained through an unidentified former Biogenesis employee. Bosch's attorney, Susy Ribero-Ayala, said in a statement the New Times report was “filled with inaccuracies, innuendo and misstatements of fact."

Rodriguez — whose name appears 16 times in documents reviewed by New Times, either as “Alex Rodriguez, “Alex Rod” or the nickname “Cacique,” a pre-Colombian Caribbean chief — admitted in 2009 that he used PEDs from 2001-03. Cabrera, Colon and Grandal were suspended for 50 games each last year by MLB following tests for elevated testosterone. Responding to the testosterone use, MLB and the players' union said Jan. 10 they were authorizing the World Anti-Doping Agency laboratory outside Montreal to store each major leaguer's baseline testosterone/epitestosterone (T/E) ratio in order to detect abnormalities.

"We are always extremely disappointed to learn of potential links between players and the use of performance-enhancing substances," MLB said in a statement. "Only law enforcement officials have the capacity to reach those outside the game who are involved in the distribution of illegal performance-enhancing drugs. ... We are in the midst of an active investigation and are gathering and reviewing information."

A baseball official, speaking on condition of anonymity because he was not authorized to make public statements, said Monday that MLB did not have any documentation regarding the allegations. If MLB does obtain evidence, the players could be subject to discipline. First offenses result in a 50-game suspension and second infractions in 100-game penalties. A third violation results in a lifetime ban.

Rodriguez is sidelined for at least the first half of the season following hip surgery on Jan. 16. A 50-game suspension would cost him $7.65 million of his $28 million salary.

If the latest allegations are true, the Yankees would face high hurdles to get out of the final five years and $114 million of Rodriguez's record $275 million, 10-year contract. Because management and the players' union have a joint drug agreement, an arbitrator could determine that any action taken by the team amounted to multiple punishments for the same offense.

But if Rodriguez were to end his career because of the injury, about 85 percent of the money owed by the Yankees would be covered by insurance, one of the baseball officials said.

Gonzalez, who posted a 21-8 record last season, denied using PEDs on his Twitter feed. Cruz denied the allegations as well and Colon was not issuing a statement, his agent said through a spokesman.

The Associated Press contributed to this report.

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