In some ways, Saturday could be looked at as the official start of the regular season for the New England Patriots and the 31 other teams in the National Football League. Saturday is the day that the regular-season roster is decided, and the 53 players on whom a team will hinge its hopes for success this season are finalized.

For better or for worse.

The way the roster looks at 4 p.m. Saturday certainly isn't what it will look like come Dec. 28, the day of the regular-season finale in Buffalo, or maybe even Sept. 28, when the Patriots are resting during their bye week. But for now, it will be the best roster coach Bill Belichick and his staff can put together for Week 1 against the Kansas City Chiefs.

Putting together the roster and deciding who stays and who goes is an ongoing process and certainly an inexact science, but here's our best guesses as to who will be sticking around come the end of the day.

QUARTERBACKS

Staying: Tom Brady, Matt Gutierrez, Kevin O'Connell

Going: Matt Cassel

From the beginning of training camp, it seemed like this would become the Battle of the Matts: Brady certainly isn't going anywhere, and the Pats will hold on to O'Connell, a third-round pick this year. So it was up to Cassel, entering his fourth year, and Gutierrez, in his second, to duke it out for the number-two spot. Despite being given every chance, Cassel has plain struggled, while Gutierrez looks confident running the offense. The one fly in the ointment could be if a veteran quarterback becomes available; Kansas City's Damon Huard has experience in the Pats' system and is a somewhat forgotten man for the Chiefs. If that happens, New England may have to either make a decision on Gutierrez, or O'Connell may come down with a mysterious Foxboro Flu that places him on injured reserve.

RUNNING BACKS

Staying: Laurence Maroney, Kevin Faulk, Sammy Morris, LaMont Jordan, Heath Evans

Going: BenJarvus Green-Ellis

On its face, keeping five backs might seem unlikely, but Belichick seemed to indicate twice this week that that's just what's going to happen. For fantasy football players, it's the ultimate back-by-committee, but for a team looking for a more balanced offensive attack, it's great. Each player has his strengths, but each can do a little bit of what the others do also. Evans is the only traditional fullback on the roster.

WIDE RECEIVERS

Staying: Randy Moss, Wes Welker, Jabar Gaffney, Kelley Washington, Chad Jackson, Sam Aiken

Going: C.J. Jones

This is pretty cut-and-dried. Moss, Welker and Gaffney figure to be Brady's top targets, with Washington and Jackson hoping for the occasional look their way. Jackson remains all potential; when Welker left last week's game against the Eagles with a rib injury, it was Washington who came onto the field with Welker and Moss in a three-receiver set. Washington is also a key special-teams player, a role Aiken was brought in for also; but Aiken hasn't been on the field since being injured in the preseason opener. Placing him on injured reserve could open the door for Jones.

TIGHT ENDS

Staying: David Thomas, Benjamin Watson, Stephen Spach

Going: Jonathan Stupar, Tyson DeVree

Keeping five running backs might lead to just two tight ends being retained, but the Pats like to use tight ends, and both Watson and Thomas have struggled with injuries in recent years (Watson hasn't practiced this week), meaning Spach sticks. The team released Stupar on Friday.

OFFENSIVE LINE

Staying: Matt Light, Logan Mankins, Dan Koppen, Billy Yates, Nick Kaczur, Wesley Britt, John Welbourn, Russ Hochstein, Mike Flynn

Going: Oliver Ross, Dan Connolly, Jimmy Martin, Stephen Sene

A veteran group with some new parts who are working their way into the rotation and trying to build line chemistry, the mainstays must be looking to redeem themselves after their performance in Super Bowl XLII. Light only recently returned to the field after missing nearly a month of practice, while Hochstein continues to miss time with an undisclosed injury. Ross may not be released, but at a minimum will be moved to the reserve/PUP list; he's currently on the active/PUP list. The team released Martin on Friday.

DEFENSIVE LINE

Staying: Richard Seymour, Vince Wilfork, Ty Warren, Jarvis Green, Mike Wright, Le Kevin Smith

Going: Steve Fifita, Titus Adams, Santonio Thomas, Kenny Smith

How many other teams can boast three Pro Bowl-caliber players on the D-line? Seymour and Wilfork have been there before, and Warren should have been there already. Toss in Green and it's a pretty formidable core. Le Kevin Smith, who should be back soon from his knee injury, and Mike Wright can play both end and nose. Fifita was released Friday.

LINEBACKERS

Staying: Tedy Bruschi, Mike Vrabel, Adalius Thomas, Jerod Mayo, Pierre Woods, Shawn Crable, Larry Izzo, Eric Alexander, Gary Guyton

Going: Victor Hobson, Vince Redd, Bo Ruud

Most of these are fairly easy; Hobson is where it gets tough. An experienced but still relatively young veteran, he seemed like the late free-agent signing that could make an impact. But he's struggled in picking up the inside linebacker role he was asked to convert to. Guyton is younger and under New England's control for longer (and less money), and has shown well.

DEFENSIVE BACKS

Staying: Rodney Harrison, James Sanders, John Lynch, Brandon Meriweather, Ellis Hobbs, Fernando Bryant, Terrence Wheatley, Jonathan Wilhite

Going: Anwain Spann, Ray Ventrone, Mark Dillard, Jeff Shoate, Mike Richardson, Lewis Sanders

Spann and Ventrone -- a sentimental favorite here to make the team -- could become high-paid practice squad players so they can stick around and help at a moment's notice. Richardson, who missed all of last year with an injury, has missed a big chunk of time and could be placed on IR again. The team released Shoate on Friday.

SPECIALISTS

Staying: Stephen Gostkowski, Chris Hanson, Lonie Paxton, Matthew Slater

Going: No one

Slater may well get the primary kick return job both due to his preseason performance and to preserve Hobbs' health, but nevertheless stays as an all-purpose special teamer. Gostkowski has been perfect in the preseason, but Hanson drew Belichick's ire for not punting out of bounds against the Eagles and the kick came back for a touchdown. Paxton is steady as always.

smanza@projo.com