GREEN BAY — Mike McCarthy has no doubt about one thing: Brett Favre will have his doubts.

Maybe it'll be in a week. Or in a month. Or after the draft. Or when training camp starts. Or on the opening weekend of the regular season. But McCarthy knows it will happen.

Favre will second-guess the decision he made Monday night to retire. He will itch to be the Green Bay Packers' starting quarterback again, just as he was for the past 16 magnificent years. He will yearn for the roar of the crowd, the adrenaline rush of eluding a blitzing linebacker and delivering the perfect strike to his receiver, as he did over and over and over again throughout this brilliant career.

"Absolutely," McCarthy, the Packers' third-year coach, said when asked whether Favre will have regrets. "Just talking again (Monday) night, we talked about the reality that he'll experience. And he was telling me about the conversation he'd shared with a family member about when the games start in the fall, it's going to probably hit him the hardest."

The question is, what will Favre do about it? He's scheduled to hold his first news conference as a retiree at 11 a.m. Thursday at Lambeau Field, and even if he pulls a Reggie White and un-retires — not that anyone's expecting that — he still won't beat his old pal the Minister of Defense, who was retired for all of 24 hours in April 1998.

White actually retired three times: the odd 1998 turn of events, when he told coach Mike Holmgren and general manager Ron Wolf that he couldn't go on because of severe back pain, only to reconsider and play one final season; after the 1998 season, when he had 16 sacks and was named defensive player of the year; and then for good after one ill-advised season with the Carolina Panthers in 2000.

Of course, White isn't alone. Sports history is littered with players who walked away, then spun on their heel with an about-face because the pull of the game they loved was too strong. Michael Jordan is the epitome of the syndrome, but football players — and particularly quarterbacks — seem to struggle with it the most.

In a story that ran in the Wisconsin State Journal's 2005 NFL preview section — now there's an indicator of how long Favre wrestled with retirement, since he played two more years after that season — Hall of Fame quarterbacks Dan Marino, Steve Young, Troy Aikman and John Elway talked about the allure of continuing to play and how difficult it was to walk away. And stay away.

Unlike Favre, who cited being "tired mentally" in his voicemail message to ESPN's Chris Mortensen, Elway said at the time that "Mentally, I wanted to do it. Mentally, I'll still want to play at 65. But I knew physically I couldn't play anymore." Elway retired on May 2, 1999 — like Favre, at age 38 — and was inducted into the Hall of Fame in 2004.

Marino, who retired at age 38 after the 1999 season, contemplated a comeback in 2000 — he received a much-publicized offer from the Minnesota Vikings, and an under-the-radar sales pitch from his hometown Pittsburgh Steelers — but decided against it.

"I probably could have played," said Marino, was the NFL's all-time leader in attempts (8,358), completions (4,967), yards (61,361) and touchdown passes (420) until Favre broke all those records. "For me, there was something special about playing 17 years at one place, and I think that is never going to change. Although I was pretty close to doing it, it just didn't feel right. Sometimes you have to go by instincts and your emotions. That's probably why I didn't do it. But I probably could have played another year — no doubt."

Young and Aikman also wanted to keep playing, even though both suffered multiple concussions in their careers. Young, who retired after the '99 season at age 38 and entered the Hall of Fame in 2005, and Aikman, who was only 34 when he retired after the 2000 season and was inducted in 2006, considered comebacks, too.

Aikman drew interest from the San Diego Chargers after his release, and the Dallas Cowboys toyed with the idea of bringing him back in 2003. Aikman told The Associated Press this week that Favre will suffer from the same retiree's remorse.

"I was ready to go, and had talked with my wife and everything about it," Aikman, now an analyst for Fox Sports, said of the possible comeback. "You want to walk out on top. But at the same time, you're walking away from something you really enjoy.

"I was glad it didn't work out, in hindsight," Aikman added. As for Favre, "When you start giving this much thought to retirement, I think that is a pretty good indicator that it's time."

McCarthy and Packers general manager Ted Thompson have drawn some criticism for not trying to talk Favre into coming back — Favre's agent, James "Bus" Cook, was particularly harsh — but both said it wasn't their place to convince Favre to change his mind. Former GM Ron Wolf agreed, saying he "never believed in that."

"I would never try to talk somebody out of doing something they wanted to do," said Wolf, who acquired Favre from Atlanta in a February 1992 trade. "If their mind is made up, it's well-thought, I don't believe you do that."

Asked if Favre might reconsider on his own, Thompson replied, "He seemed to be at peace with his decision. But as I've also said, it's a very complicated decision process that he has go to through on this. I guess you never say never, but I wouldn't anticipate (a comeback)."

If Favre did change his mind, "somebody would find a place for him," retired Packers president and CEO Bob Harlan said with a smile. But Harlan, for one, doesn't expect it to happen — "I would assume he's given this a lot of thought, and I've always felt (his wife) Deanna would have a lot to say about it when the time came," Harlan said — nor does he hope it happens.

Not that he wouldn't love to see it, deep down.

"I always told people I thought it was such an honor to watch him play, and (that) we're all going to look back some day and say how fortunate we were to see Brett Favre and this wonderful career," Harlan said. "And that the last time he went down the tunnel would be a sad day for the Green Bay Packers, but it would also be a sad day for the National Football League. And I truly feel that way.

"(But) we've (all) seen a lot of great, great athletes who decide to try that one more year and it's a disappointment. I've always felt badly that Reggie came back and played that year at Carolina because he wasn't the same Reggie White. And I think it'd be very sad to see (Favre come back and say), 'This wasn't the same Brett Favre.' He has been so magnificent. He went out on top: great season, great team record. It's a great way for him to exit and add to his legacy."