Editor's note: The 2012 NCAA baseball tournament bracket will be unveiled on Monday, May 28 at noon ET on ESPNU.

As most schools head into conference tournaments, there isn't much time left to impress the selection committee. What's at stake over the last week of the regular season for at-large and top-seed contenders?

ACC tournament (Greensboro, N.C., May 23-27): Two teams from the conference are likely to earn national seeds. Florida State is a lock, and North Carolina has the inside track over NC State based on its overall résumé, though a Wolfpack run to the title game could shift the balance. Those three are all locks to host regionals and will likely be joined by Virginia. Though it's unlikely to happen, the Cavaliers could be overtaken by a fifth SEC team or UCF when hosts are announced, especially with a subpar performance in Greensboro.

Miami and Clemson are safely in the NCAA tournament. Georgia Tech and Wake Forest are on the right side of the bubble, but either could fall off with an 0-3 week and upsets elsewhere. Maryland and Virginia Tech have strong overall bodies of work, but without a chance to impress in the ACC tournament, they're likely to meet the same fate as LSU last year and be left sitting at home in June.

Big 12 (Oklahoma City, May 23-27): Baylor lost four of its last six conference games after starting 18-0 in Big 12 play, but is still a slam dunk as a national seed. Texas A&M is a lock to host, and a conference tournament title could get it into the national seed discussion. Oklahoma's late surge, especially the sweep against Baylor, has the Sooners pretty safely off the bubble. Texas is an interesting case after finishing third in the conference but with a weaker RPI than the Sooners. The Longhorns should be in, but a couple of wins in Oklahoma City would make it easier to sleep.

Big East (Clearwater, Fla., May 23-27): Louisville won a share of the regular-season title and has an RPI that places it firmly on the right side of the bubble. St John's was the co-champion, but lost the season series to the Cardinals. The Red Storm are in much the same position as last year when they received an unexpected NCAA tournament bid. A few wins in Clearwater would make them breathe easier on selection day on Monday. The only route for the other six teams in the tournament is to win the automatic bid.

Big South (High Point, N.C., May 22-26): Regular-season champion Coastal Carolina has a regional invite wrapped up. The rest of the conference is looking to burst someone else's bubble by taking the conference tournament.

Big Ten (Columbus, Ohio, May 23-26): Even after dropping its final series of the year against Iowa, Purdue is safely in the field and still a likely host. A quick exit from the Big Ten tournament might mean the Boilermakers are hosting as a No. 2 seed, though. Michigan State's at-large status depends on the committee; if it emphasizes road record and other factors over RPI for northern teams, as it did last year, the Spartans have a good chance to make the field. The rest of the field in Columbus needs to win the automatic bid to keep playing.

Big West: There is no conference tournament in the Big West, but the top two teams meet in the final series of the year. Cal State Fullerton travels to Long Beach State, with the winner of the series claiming the automatic bid. The Titans took two of three in a nonconference series earlier in the year. Fullerton needs to win the title to host a regional, but even then could be squeezed out by a fourth Pac-12 team.

Colonial (Harrisonburg, Va., May 23-26): UNC Wilmington should be playing in June regardless of how it plays at the conference tournament. The other five teams need to win the automatic bid to keep their season alive.

Conference USA (Pearl, Miss., May 23-27): Rice and UCF are safely in the NCAA tournament. With a tournament title to go with its regular-season crown, Rice could be in the discussion for a national seed. UCF is in the mix to host a regional, especially with a solid run in Pearl. East Carolina finished sixth in the conference, but unless the Pirates go 0-3, their RPI should land them a regional spot. Tulane needs a solid tournament run, and even that might not be enough if there are lots of upsets elsewhere.

Great West (Orem, Utah, May 22-26): Utah Valley saw its winning streak come to an end at 32 games, but finished 28-0 in conference and should breeze through the conference tournament at home. Their inclusion in the projections this week is more an indication of how weak the bubble is -- they'll be the first team knocked out of at-large consideration when a lower seed from a mid-major conference steals a bid.

Missouri Valley (Springfield, Mo., May 22-26): Indiana State won the regular-season title but has the worst RPI of the top three teams. Missouri State won the season series against the Sycamores and has the best RPI in the league. That should ensure two bids for the league. Wichita State and Illinois State are both in the at-large discussion with solid RPI numbers, and the Shockers' overall body of work might be good enough to land a third bid, especially with a strong tournament showing. Illinois State and the other four teams in the conference need to win the tournament title.

Mountain West (Las Vegas, May 24-27): New Mexico and TCU finished the season tied for first and split six regular-season meetings. TCU is in a regional regardless of how it does at the MWC tournament but the Lobos likely need to win in Las Vegas, or at the very least make the title game. They are in as the auto bid this week, and would be vulnerable to upsets elsewhere without it.

Pac-12: One of three conferences with no tournament, the title comes down to the final weekend. Oregon leads Arizona by a game, with UCLA and Stanford lurking just behind them. None of the four play each other in the final weekend, as the slate wraps up with each team playing its natural rival. The Ducks (league leader) and Bruins (top RPI in the nation) are best positioned for national seeds. Along with those two, Stanford is pretty secure as a regional host heading into the final series. Arizona, which is battling Cal State Fullerton among possible hosting locations, finishes with a home series against Arizona State. Oregon State is safely in the tournament, while Washington has gone 1-6 over the past two weeks and needs to bounce back against Seattle and Washington State to stay on the right side of the bubble.

SEC (Hoover, Ala., May 22-27): LSU (regular-season title) and Florida (best RPI in the best conference) should be national seeds even if they go two-and-out. South Carolina could use a couple of wins to wrap up a national seed, depending on results elsewhere. Kentucky, Arkansas and Mississippi State are playing to host regionals. The Wildcats are in the best position, but a late slide has made them vulnerable. Ole Miss is safely in the NCAA tournament, and Vanderbilt should be in unless there are numerous mid-major upsets. At this point, it looks like only a trip to the title game would get Auburn or Georgia into a regional if the committee uses the same emphasis as last season.

Southern (Greenville, S.C., May 23-27): Regular-season co-champions Appalachian State and College of Charleston can breathe easy -- both should hear their names called on selection day whatever happens the final week. Elon and Samford are both on the wrong side of the bubble; a run to the title game would help, but a tournament title and auto-bid is the only way either would be truly safe.

Southland (San Marcos, Texas, May 23-26): If the past is any indication, nobody is safe at the Southland Conference tournament. Sam Houston State won the regular-season title by four games and has an RPI in the top 50, but teams with similar résumés have missed out after going 0-2 in the Southland tournament, leaving the Bearkats in a safe position but with work still to do. Southeastern Louisiana has just as good a résumé but no regular-season title, so a few wins in San Marcos would help. Tournament host Texas State is still in the discussion and a run to the title game could net it an at-large bid.

West Coast: Like the Big West, the WCC doesn't have a conference tournament. Also like the Big West, the schedule-makers got it right. Pepperdine and San Diego head into the final weekend tied atop the standings, with the Toreros traveling to Malibu, Calif., to take on the Waves. Both teams should be safe on selection day regardless of who wins the series. Gonzaga has played its way out of the field over the past month, and even a season-ending sweep of BYU is likely to be enough to get them on the right side of the bubble.

Jeremy Mills is a researcher for ESPN and is a contributor to ESPN.com's college baseball coverage.