It doesn't take a rocket scientist to determine what continues to be the hottest question on the NFL head-coach/GM rumor front:

Just what will those heavy-hitter "rock stars" currently sitting on the sidelines really be doing in 2010?

With their impressive track records looking increasingly appealing to a number of teams, the quartet of Mike Holmgren, Mike Shanahan, Jon Gruden and Bill Cowher has become the NFL's answer to The Beatles, with speculation on each of their immediate futures starting to pick up steam as the 2009 season begins its stretch drive.

What follows is the latest conjecture on "the Big Four," beginning with Holmgren and some breaking news in Seattle:

The way we hear it from well-connected sources, Seahawks GM Tim Ruskell, who has been under increasing fire in the Pacific Northwest and is in the final year of his contract, has been informed that he will not be returning next season.

Enter the 61-year-old Holmgren, who has been rumored for a while now as a strong bet to return to Seattle strictly as the head of football operations. Holmgren, who reportedly has also been pursued by Browns owner Randy Lerner, now appears much more likely to try to reinvent himself in Seattle, where he served as the head coach from 1999-2008 and — in the first four years — also as the team's executive vice president and general manager.

Holmgren hardly distinguished himself in a dual head coach-GM role and was squeezed out of his executive role after the Seahawks compiled a lackluster 31-34 record (including the playoffs) under his direction with only one playoff appearance.

With Ruskell entering the fray as the new GM in 2005 and Holmgren serving solely as the head coach, the Seahawks enjoyed considerably more success through the remainder of Holmgren's previous stint in Seattle, as the Seahawks went on to compile a 59-46 record with four division championships in six seasons and a trip to the Super Bowl in 2005.

On more than a few occasions, Holmgren has acknowledged the difficulty he had in handling a dual head coach-GM role and how much he now recognizes the error of his ways the first time around as a GM. Team insiders tell us his biggest error was his obsessive micromanaging and tendency to want to do everything himself. League insiders, meanwhile, have been wondering aloud recently whether or not Holmgren would be able to avoid trying to steal the thunder of whoever would be serving as the team's head coach.

The indication currently is that Jim Mora, who is in his first year as the Seahawks' head coach, would probably remain on the job under Holmgren.

"You would think the two of them could work well together," said one team insider. "Mora has mentioned more than once how much he learned last season (as the Seahawks' assistant head coach and secondary coach) watching the way Holmgren handled himself in his final year."

But the way we hear it, it would not be a shock if Holmgren made a concerted effort to lure Gruden away from his recently extended contract with ESPN and team up with his former Green Bay assistant for what would be an eye-popping parlay.  

In a Holmgren-Gruden scenario, we hear Holmgren might consider making (VP/player personnel) Ruston Webster the Seahawks' GM, given how well Webster previously worked together with Holmgren.

"But Gruden and Webster never saw eye to eye in Tampa (when Gruden was the Buccaneers' head coach), in part because they would not let Webster out of his contract to join Ruskell in Seattle in the first place," said a league insider. "A Gruden-Webster pairing would not work, creating a need for another GM or head coach."

It's very much worth noting that it was at roughly this point in the season in 2002, Holmgren's final year as the GM, that his team caught fire and won four of its final six games, including its last three games — a piece of interesting recent history pointed out by Danny O'Neil of the Seattle Times last week. That successful late-season run set the table for the great success that was to follow in Seattle the next five seasons.

Could Holmgren be successful the second time around in Seattle if he is indeed back in the driver's seat?

Many of our sources aren't so sure.

"There are some in Seattle suggesting that the team should take the blinders off (in pursuit of Holmgren and perhaps consider a young, up-and-coming guy to run the team instead," said one team insider.

Added a league executive: "Mike Holmgren is a name. He doesn't know what to do with (acquiring) personnel."

That league exec's assertion is debatable. While it's true Holmgren drafted more than a few lemons as Seattle's GM (Lamar King, Koren Robinson, Jerramy Stevens), he also had his share of plums (Steve Hutchinson, Shaun Alexander and, most notably, Matt Hasselbeck, whom he acquired in a trade with Green Bay).

In any event, it's really beginning to look like a return to the Seahawks is on the horizon.

As for a possible hookup with Gruden, we hear that while such a pairing would be undeniably intriguing, it is far from a done deal.

"The only question with Gruden — that even head coaches around the league cannot figure out — is why he extended with ESPN long term," one league insider told PFW. "He was flying in a lot of college coaches running the spread in the offseason and picking their brains, watching tape for six hours and then going golfing with them later in the day.

"He even flew in Tom Moore when he was misaligned with the Colts (because of pension issues). So he really may be enjoying his time away from the game, and few are convinced he is returning, with several years still left on his Tampa deal. He does love (Florida QB and Heisman Trophy candidate Tim) Tebow, though. He has been studying the spread offense, and Seattle needs a QB. And Seattle is known as one of the three highest-paying organizations in the league."

On the other hand ...

"I don't know that Gruden wants back in," an NFL personnel director told PFW. "He just signed that big extension with 'Monday Night Football.' That might be saying he wants to keep studying the game from afar for a couple more years and get a better grasp on the game — to get his doctorate degree in football from the best coaches around the league and wait for the right opening. ... The guy is always asking questions and always learning."

Moving on to Shanahan and Cowher, we hear that, in both cases, they will follow the money trail and look for the most lucrative offer available. While Shanahan has made no bones about his desire to get back into the NFL mix, Cowher continues to bide his time, most recently claiming on the CBS pregame show on Thanksgiving Day that he won't openly pursue any head-coaching offers until vacancies officially open at the end of the season.

Shanahan, who compiled a 146-91 record in 14 seasons in Denver but was only 24-24 in his final three seasons as head coach, met for seven hours this past Monday night and Tuesday morning in the Mile High City with Bills chief operating officer Russ Brandon regarding the Buffalo head-coaching job, which opened up recently with the firing of head coach Dick Jauron.

Not surprisingly, both Shanahan and Brandon indicated they were in no rush at all to consummate a deal, one which league insiders believe would have to at least match the $20 million still owed to him over the next three years by the Broncos.

"Shanahan met with Buffalo, but I doubt he wants to take his offense up to the cold, not with the roster they have there," an NFL personnel director told PFW. "It's not in top shape. They (the Bills) are small in a big division. Very average in talent. I'd have a very hard time patting myself on the back if I put that one together."

What could end up being a lot more likely for Shanahan, we hear, is a new gig in Washington, given the multiple meetings that took place between him and Redskins owner Daniel Snyder earlier this season, Snyder's willingness to overspend, and the ties that exist between Redskins executive VP of football operations Vinny Cerrato and Shanahan from their days together in the 49ers' organization.

There are also rumblings, although not nearly as strong as those in Washington, that the Bears could possibly consider hiring Shanahan — a natural marriage in the eyes of many, with Shanahan having grown up in the Chicago area as well as having groomed beleaguered Bears QB Jay Cutler.

"Chicago's roster has slipped in recent years," said one NFL talent evaluator, "but they do have a quarterback (in Cutler). Shanahan showed he can coach the guy.

"Going from Shanahan to (Bears QB coach) Pep Hamilton ... is a huge step back, and it's clear it has frustrated Jay Cutler. The Bears need to invest more heavily in someone who can get Cutler back on track."

As for Cowher, who flirted with the Browns and Jets last year, there really don't appear to be any serious head-coaching offers on the table, although there was a recent NFL Network report that he would be "excited" by potential openings in Houston and Chicago.

PFW also reported recently that higher-ups within the Bears' organization have casually reached out to an intermediary of Cowher to assess his interest level, although there is no tangible evidence that Bears head coach Lovie Smith is in any danger of losing his job with two years and $11 million still remaining on his contract.

Cowher, who has a home in North Carolina, has also been frequently linked with the Panthers, but our sources aren't putting much stock in that potential connection.

"(Panthers GM) Marty Hurney has been told the front office is safe and he is returning, and he's a loyal guy," said one source. "I could see offensive coordinator Jeff Davidson getting shipped out, given their frustrations with him, but I would be a little surprised if (head coach John) Fox was let go, unless the team finishes very poorly down the stretch.

"(Panthers QB Jake) Delhomme is a favorite of the owner, and Hurney is under no heat for extending him, so that could potentially eliminate Carolina as a Cowher destination.

"And Texans GM Rick Smith was extended last summer until 2012 and is expected to be allowed to pick his own coach, which would eliminate Cowher for an opening in Houston if he cannot bring in his own people, provided there is even a coaching opening."

Which would leave — perhaps with a capital "M" — the Bears.

"While the McCaskeys were running the team, it was (Mike) Ditka, (Dave) Wannstedt and maybe — if they take back ownership — Cowher," said one league source. "Blue-collar town, blue-collar guy, passionate football city.

"It makes sense and fits like a glove on many levels."

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