ABC News' Paula Faris and Aaron Katersky report:

Major League Baseball has informed the union which players it intends to punish for obtaining performance-enhancing drugs from Biogenesis, the now-defunct clinic in South Florida first named as a supplier by the Miami New Times, ABC News has learned from a source close to the investigation.

Alex Rodriguez is reportedly among the players who could face suspension.

He did not answer questions today in Tampa, where he continues a rehabilitation stint at the Yankees' training facility. Rodriguez, arguably the biggest star with the biggest salary at $28 million for the season, has not played since October because of an injury.

"Baseball is trying to drop the hammer as hard as it can," said Tim Kurkjian, an ESPN analyst for "Baseball Tonight." "MLB is going to try to ban A-Rod for life but if they do, they know they'll get in an incredible fight with the union."

Players union representatives started today to inform the targeted ballplayers whether they have a right to appeal or whether it's better for them to accept a plea deal as Ryan Braun did.

Braun, 29, was suspended July 22 for the rest of the season - 65 games - for using the banned substances he'd denied using for nearly two years. He stands to lose $3 million of a nearly $9 million salary.

According to ESPN, Rodriguez might face a harsher punishment than Braun. He allegedly did not only violate the league's drug policy but also reportedly tampered with evidence.

While most of the players involved in the probe are expected to accept their suspensions and punishments, Rodriguez's legal team has repeatedly said it will appeal.

"We believe we have good, solid and strong defenses for Alex and we intend to present them when the times comes," David Cornwell, Rodriquez's lawyer, said in an interview with ESPN New York radio.

Once the players are informed, the MLB will publicly announce the suspensions, likely by paper statement and likely by the end of the week.

According to the source, the league wants to do this before there are fewer than 50 games remaining on the schedule so the suspensions do not drag into the next season.