Sources: Alex Rodriguez, Ryan Braun main targets of MLB's probe of Biogenesis clinic

Major League Baseball is honing in on Alex Rodriguez and Ryan Braun as two main targets for potential discipline as it prepares to interview players about the Biogenesis clinic that allegedly distributed performance-enhancing drugs throughout the game, sources with knowledge of the league's investigation told Yahoo! Sports.

In addition to being the two biggest names in the Biogenesis logbooks, Rodriguez and Braun have in the past provided MLB with information about alleged PED use the league believes to be false, prompting the extra scrutiny, according to the sources. Following the admission he had used steroids from 2001-03, Rodriguez said in an interview with the league he had not since used any PEDs. Braun maintained his innocence after testing positive for synthetic testosterone during the 2011 postseason. An arbitrator overturned a suspension based on chain-of-custody issues with the urine sample.

"There's no question in my mind they want those two guys," one source involved told Yahoo! Sports.

In pursuing non-analytical positives, which under the league's Joint Drug Agreement could prompt 50-game suspensions, MLB can take into account a number of factors, including evidence such as the players' names appearing in the Biogenesis documents along with past history of cooperation.

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During the nascent stages of its investigation into the Miami-area clinic, MLB has targeted three separate camps: players connected to the University of Miami, where Braun played in college; players connected to Rodriguez, who the Biogenesis documents obtained by the Miami New Times paint as a central figure; and players connected to the ACES sports agency, which has had 10 players named publicly. Investigators have spent equal amounts of time looking into the three threads, two sources told Yahoo! Sports.

The union has broached the idea of a joint investigation into Biogenesis with the league, according to sources, though one official maintains MLB plans to conduct the investigation itself. MLB expects the union to appeal any potential penalties to players associated with Biogenesis.

Any case against Rodriguez and Braun will need more evidence than provided by the logbooks to hold up against an appeal, officials have acknowledged, and while they're hopeful the investigation will provide it, they're uncertain whether it will come directly from players.

Multiple sources said the league has discussed offers of immunity to major league players, though none has been officially offered. The league and union continue to negotiate over the conditions. MLB would like information beyond players admitting they used PEDs. The union, according to sources, plans to keep players from pointing fingers at one another. Immunity deals would target only players whose connection with Biogenesis could prompt a suspension under the league's drug plan.

Through the interviews, which sources expect to begin after spring training ends, the league plans to at very least seek information on Biogenesis and its founder, Anthony Bosch, to form a fuller picture of the scope of his alleged PED distribution.

MLB and union officials declined comment when reached by Yahoo! Sports.

Bosch is under investigation by the Florida Department of Health as well, according to the New Times. MLB's investigation could get a further boost from information gathered by the government.

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More than two dozen baseball players' names have surfaced publicly, and USA Today reported Wednesday at least 90 appear in the Bosch's logbooks. The league has interviewed players not on 40-man rosters, and one such player told Yahoo! Sports he was offered immunity in exchange for information about Biogenesis. Another player interviewed, Cesar Carrillo, was suspended 100 games after MLB deemed his cooperation unsatisfactory.

Carrillo, who was Braun's road roommate in college at the University of Miami and remains his friend, showed up on the same page of a Biogenesis document obtained by Yahoo! Sports that lists Braun's name next to a due payment in the range of $20,000 to $30,000.

Braun said the payment was a consultation fee for Bosch on the appeal for Braun's positive test. Rodriguez has said he had no relationship with Bosch or Biogenesis.

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