Given the potential length of an appeal process for the players involved, Alex Rodriguez, Ryan Braun, Nelson Cruz and the other principal players in the Biogenesis investigation could be in limbo into the offseason.

Weiner also said the commissioner's office isn't bound by the terms of the joint drug prevention and treatment program -- which calls for 50- and 100-game suspensions and a lifetime ban for three failed drug tests -- because the players involved in the Biogenesis case did not fail tests and are being investigated for "non-analytical" reasons.

Much of MLB's case is being built on phone records, receipts and other information provided by Anthony Bosch, the founder of Miami-based Biogenesis of America anti-aging clinic.

"In theory, [the players] could be suspended for five games or 500 games, and we could then choose to challenge that," Weiner said. "The commissioner's office is not bound by the scale we have in the basic agreement."

A provision in the drug-testing agreement gives the commissioner's office the latitude to announce suspensions before they are appealed if the cases are already public knowledge, but the union is expected to mount a challenge in the Biogenesis case.

Weiner indicated that the union will advocate that suspensions remain private and confidential until the players' appeals before arbitrator Fredric Horowitz are complete.

ESPN's "Outside the Lines" has reported that Rodriguez and as many as 20 other players are expected to be suspended for their relationship to Bosch, who allegedly provided performance-enhancing drugs to the players. Rodriguez has denied the allegations.

When asked directly on Monday about his involvement with Biogenesis, Rodriguez said: "I appreciate you asking that question. But due to the process, we're not allowed to comment on that. But with due time, we'll talk about that."

Commissioner Bud Selig, in his annual All-Star Game talk to members of the Baseball Writers' Association of America, promised a "thorough, comprehensive and aggressive" investigation into the Biogenesis scandal, saying that MLB is committed to getting it right regardless of the time frame or the potential impact on affected clubs.

"I'm sensitive to that, but we have to complete this investigation," Selig said. "I have to see the results, and then we're going to move forward. Those are the only concerns."

Selig has come under fire through the years for baseball's tardiness in addressing the PED issue but issued a spirited defense Tuesday of the strides the game has made.

The Biogenesis case has been perceived as yet another black eye in a steroids narrative that goes back to the Mark McGwire-Sammy Sosa home run race in 1998.

"People are sometimes critical of baseball and say a lot of different things," Selig said. "They say this [case] is about retribution or my legacy -- whatever the case may be.

"We went through the cocaine era of the '80s and there was no drug-testing agreement, which was quite sad. The Pittsburgh drug trials -- very sad, and still no drug-testing agreement. Now here we are, 30 years later with the toughest drug testing agreement in American sports. We must be doing something right. I haven't heard from anyone in Washington in eight and a half years."

Bud Selig said MLB administered 4,200 random drug tests last season at the major-league level and 16,000 tests overall between the majors and the minor leagues. AP Photo/Pat Sullivan

Selig said MLB administered 4,200 tests at the major league level last year and 16,000 tests overall between the big leagues and the minors. He said MLB testing produced seven positive results, and the overall failure rate was less than half of 1 percent.

Selig also cited the banning of amphetamines as a positive step and said team trainers and doctors have told him that baseball is doing "fine." But he also expects stiffer penalties for PED use to be a topic of discussion in the next collective bargaining agreement.

"I had a player come to me a few months ago who wanted me to know how much he and many others resent it being called the steroid era, because a great, great majority of our players never did it," Selig said. "It puts them in a very difficult position."

Selig also appeared Monday night on the "Late Show with David Letterman," saying "only time will tell" when asked whether Rodriguez would play for the New York Yankees again.

"We're in the midst of a very thorough and tough investigation on all of this, because I really believe it's not only the right thing to do, we're going to do it," Selig said.

But Selig danced around the topic of whether Rodriguez faces a suspension, saying: "I'd rather not say."

"But you know, don't you? I can tell," Letterman asked.

"I do. The answer is, I do," Selig said before drawing applause from the studio audience.

Selig also said the issue of Rodriguez's contract would be for the Yankees and the third baseman to work out, although he added that the sum of money in question would not be "incalculable."

"It's over $100 million, and it's been calculated by everyone," Selig said.

Although the Biogenesis case dominated Tuesday's annual All-Star Game question-and-answer sessions held by Selig and Weiner, it was one of several topics of discussion:

Weiner, who has been dealing with an inoperable brain tumor, addressed the baseball writers from a wheelchair. He said his condition has deteriorated in the past month and that he is currently taking an experimental drug typically used to treat melanomas.

Weiner said the players' association has been discussing possible contingency plans in the event that his health prevents him from continuing with his duties but dismissed recent reports that former union leaders Donald Fehr and Gene Orza might return in leadership capacities.

Both Weiner and agent Scott Boras have decried the news leaks in the Biogenesis case as a violation of the drug-testing agreement. Selig vigorously denied that Major League Baseball has been the source of any leaks.

Information from The Associated Press was used in this report.