Weiner, 47, a Williams College alumnus and a 1986 graduate of Harvard Law School, joined the union in 1988. Since then, he has stood alongside Fehr, spending the past 10 years administering and enforcing the union's Basic Agreement as general counsel.
"I think everybody has been kind of anticipating this," said Braves outfielder Jeff Francoeur. "During the speech they give in Spring Training the past two or three years, Michael Weiner has done most of the talking. I think Don has been grooming him to take over. He won't have the experience that Don had. But he's a pretty sharp guy, and I don't think we'll skip a beat with him."
Should the players vote him their new executive director -- and every early indication is they will -- then they will have elected a man intimately familiar with the union's inner workings.
"Michael has been at my side during all the battles we have fought over the last 20 years and has been a major part of our successes," Fehr said in a statement released late Monday afternoon. "He is clearly the most qualified person to become the next executive director, and carry on the work of the Players Association in the years to come."
"I have no hesitancy in recommending to the players that he be given the opportunity to do this job," Fehr said.
Marvin Miller, who was the union's executive director from 1966-82, said "I think that he's experienced in a way that people who have become directors in the past never have been," Miller said. "He's been with the union for 21 years -- that's a tremendous advantage and I think it's a good sign. I consider him a very bright man."
Weiner did not immediately return a telephone call placed to his office.
Since ascending to his current post in 1994, Weiner has been in charge of all legal matters involving the union. Long considered the heir to Fehr's throne, Weiner has played a major role in collective bargaining negotiations over the past few years.
"Michael is a very intelligent person, and all the players are happy, and all the players indicated that he would be the next guy," Marlins union representative Wes Helms said. "It's all in place now. He's going to follow the steps of Don, and he's definitely got the tools and intelligence to do that. He will do an excellent job. I'm very confident of that."
Orioles pitcher Jeremy Guthrie, part of a player subcommittee briefed on Fehr's retirement more than a month ago, also lauded Weiner.
"I think the obvious choice was moving forward with Michael at the helm, because he's been there for the last 20 years and is just so well prepared," Guthrie said. "He's such a bright individual and is very knowledgeable about the issues that surround the players union and the game of Major League Baseball. We're very excited to have him take a larger role in the union, and we know that he'll be very good at what he does."
While immensely respected within the union, Weiner is likely unrecognizable to the average fan.
Two years ago he told USA Today that, "I've never had to use an alias on the road. I've never been stopped by a fan. No one knows me. I love it."
That figures to change in a big way if Weiner becomes the face of one of the most powerful and high-profile unions in the country. A fan of casual attire and working in the background, Weiner will have to adjust, and those who know him do not have any doubt that he will.
"The perfect guy to step in," Dodgers infielder Mark Loretta said. "He's been there for 20 years. He might be even more intellectual than Don. Don was good in front of the cameras and on Capitol Hill, and Michael isn't into that. But he's as sharp and prepared. He wears Converse, those Chuck Taylors. I've been nothing but impressed."
The New Jersey native has been praised for his ability to deal with different constituencies.
"I'm confident Michael will be great at leading us through the next decade without any work stoppages," Texas pitcher C.J. Wilson said. "He's a really cool guy. I like him a lot. He has a good relationship with the players and their agents and he carries a lot of respect."
Though a union board and the players still need to approve Weiner as executive director in a vote that should happen soon, most considered that merely a formality.
"I anticipate that the elected members of the Executive Subcommittee will recommend to the full Board that Michael become the next Executive Director," Fehr said in his statement. "If the full Board agrees, I will urge that this important decision be submitted to a full membership vote."
Weiner also played a major role in the contract agreements in 2002 and '06 that allowed the league to avoid work stoppages. The Hockey News reported in Septempber 2007, that Weiner, who has worked with the NHL players' association on arbitration matters, was on a short list to become that union's executive director -- but as Fehr's likely successor, he didn't want the job.
Two years later, Weiner appears to have his preferred position well within his grasp.
"He is very intelligent, very seasoned," said D-backs first baseman Tony Clark, an associate player representative on the union's executive board. "He is equipped to handle any and all situations that the union is involved in."