1. OKLAHOMA

44-15, 17-11 Big 12, 9-1 last 10

At their best: When Garrett Buechele is leading the offense, and their relievers carry them home. Third baseman Buechele is a true power hitter with amazing consistency. He can change a game with one swing, especially with the Sooners having several hitters who get on base. Oklahoma's starting pitching staff is OK for a tournament team, but they have three relievers in Erben, Rocha and Mayfield who can all pitch several innings to secure a win.

At their worst: They're no better than Cal. The Golden Bears can match up favorably with Oklahoma through the first two starters and also have a very deep hitting lineup. The Sooners didn't control their conference the way most No. 1 seeds did, as Texas was easily the best team in the conference (sweeping OU by 16-3 combined score). As it stands, however, they are the best team in a weak region. They should advance if they stay focused and get a boost from the home crowd.

Biggest strength: The Sooners' three right-handed relievers (Erben, Rocha and Mayfield) don't do anything unusual. None are strikeout machines, but all have low ERAs (4.10, 3.02, 2.03, respectively). It's like having a fresh starter, and they all can be counted on to stifle opposing batters.

Last NCAA appearance: 2009 (Regional)

2. CALIFORNIA

29-23, 13-14 Pac 10, 2-8 last 10

At their best: Sporadically, when their offense is clicking. The Golden Bears were a bad team at the end of the year, as they were soundly swept by UCLA, Washington State and Stanford. But when you look at their quality wins, it's hard to know what to make of Cal. They swept Oregon State late in the year and took two of three games from Oregon last weekend. The Golden Bears can score runs, but they can't prevent runs vs. top teams like most top seeds can.

At their worst: In tough games. The Bears don't really have the necessary wins against a UCLA or Arizona State to be considered an elite team. They're above-average in most categories and played in a tough conference, and it resulted in a two seed. They could surprise, but it won't be because they dominated one aspect of every game. It will be because they limited mistakes and Oklahoma struggles.

Biggest strength: A versatile offense with eight hitters batting at least .300. Tony Renda leads the Golden Bears in average (.365), runs (52) and hits (76). Cal has four players with an on-base percentage in the .400s, but Chadd Krist and Mark Canha can also hit home runs (10 and 9, respectively). It take a great pitcher to silence Cal's bats.

Last NCAA appearance: 2008 (Regional)

3. NORTH CAROLINA

36-20, 14-16 ACC, 7-3 last 10

At their best: The Tar Heels have looked really good, although they were swept by Virginia late in the season. They came up just short of qualifying for the ACC tournament because of early conference losses. North Carolina swept Virginia Tech, swept Wake Forest and took two of three at Clemson late in the season. They could be a threat to steal the region if a capable pitcher steps up in their second or third game.

At their worst: National powerhouses Virginia, Georgia Tech and Miami all swept North Carolina this season, but that's not indicative of the Tar Heels' individual talent. Thankfully, there isn't much to be intimidated about in the Norman Regional. Oklahoma is a better all-around team and Cal has a stronger offense, but North Carolina's 4.21 team ERA ranks in the top 25 nationally. Oklahoma isn't that much better (3.79, 16th nationally), and the teams could be even if Oklahoma uses too much relief talent in an early game.

Biggest strength: Starting pitcher Matt Harvey has a 3.10 ERA and has pitched two complete games. He might be the best pitcher in the region. But all hope will be lost if the Tar Heels can't get a win with him on the mound.

Last NCAA appearance: 2009 (CWS)

No. 4 ORAL ROBERTS

35-25, 22-9 Summit, 8-2 last 10

At their best: The moment Nick Ballgod or Tyler Saladino make contact. The Golden Eagles have a wealth of hitters, and Ballgod and Saladino are the best. They will find a way to produce runs, but whether that means two runs or 10 depends on the opposing pitcher. Their run production was lower against competition from TCU, UCLA, Texas and Arkansas. But they beat the Longhorns, 3-2, showing they could be a tough out.

At their worst: ORU's pitchers have pedestrian ERAs and aren't a very good fielding team. But be assured, they'll go down swinging.

Biggest strength: Ballgod has one of the most ridiculous stat lines in the country: .396, 78 hits, 53 RBIs. But teammate Saladino can beat him: .381, 72 runs, 91 hits, 17 home runs, 73 RBIs, .678 slugging percentage and 16 of 18 stolen base attempts. They're the stuff of nightmares for an unprepared pitcher or cold reliever.

Last NCAA appearance: 2009 (Regional)