Four lessons to take from the first Saturday in March

Four things we learned on college basketball's final regular-season Saturday ...

1. Thank North Carolina for putting the bracket more in flux -- and giving us some serious intrigue on the top lines heading into Championship Week. Ohio State and Kansas should be considered near-locks for the first two No. 1 seeds, and Duke would've been in good shape had it swept the Heels and won the ACC regular-season title. But now there are four teams -- Pitt, Duke, Notre Dame and BYU -- fighting for the final two No. 1s.

Pitt is in excellent shape, having captured the Big East regular-season title by grinding out a win over Villanova on Saturday. The only thing stopping the Panthers from being a total lock is that they lost two of their last five and only have one quality out-of-league win (over Texas). One Big East tourney win should do the trick. The Irish have even more at stake at Madison Square Garden, as they could make a run at a No. 1 by winning the whole thing, or even just reaching the finals. They have a killer résumé, with 10 top-50 RPI wins (including Pitt, Wisconsin, Georgetown and UConn twice) and zero bad losses. Duke meanwhile, needs to win the ACC tourney to feel truly safe as a top seed.

And what about BYU? Conventional wisdom, following this week's suspension of Brandon Davies and the ugly loss to New Mexico, was that the Cougars no longer had a shot at a No. 1 and might not even earn a No. 2. But they righted the ship to rout a bad Wyoming team on Saturday, and what if they dominate the Mountain West tournament in much the same way they did the regular season, sending a message that the loss of Davies isn't actually a big deal? BYU would be No. 3 in the RPI and own a sweep of the No. 4 RPI conference. If that's the case, it would have to receive the top seed and placement in Anaheim.

2.These three teams had the worst days on the bubble:

• Baylor. That home loss to Texas put the Bears off the bubble and into the NIT. Their résumé (RPI in the 70s, with two wins over Texas A&M and nothing else) is terrible, and they lost four of their last five heading into the Big 12 tourney. They'll need to pull off a miracle to get the league's automatic bid.

• Michigan State. The consensus among the preeminent bracketologists -- Andy Glockner and the like -- is that the Spartans are still in the Field of 68 after Saturday's loss to Michigan. But how safe are they, really? I'm worried about them if they don't win two games in the Big Ten tournament. They're 16-13 overall and 9-9 in the league, with one great win (over Wisconsin) on their résumé.

• Virginia Tech. Speaking of teams with weak résumés clinging to one good win ... the Hokies are once again on shaky ground heading into the ACC tournament. Saturday's loss at Clemson moved them to 19-10 and 9-7 in the ACC with an RPI in the high 60s. They have zero quality out-of-conference wins, one decent league win over Florida State and one big win over Duke -- that's it.

3. These three teams had the best days on the bubble:

• Butler. The Bulldogs aren't a lock to make the field after Saturday's win over Cleveland State in the Horizon League semifinals, but they do now have four wins over top-50 RPI teams (Florida State and Cleveland State three times), and have closed the season on an eight-game win streak. I think they're in as a 12 seed, potentially in one of the Dayton "First Four" games. And if it does come down to Butler vs., say, Georgia for one of the last spots, you wonder if the fact that the Indy kids were in last year's title game and were darlings of last year's tournament will matter. The committee will certainly say it doesn't matter at all ... but you still wonder.

• Michigan. The Wolverines still have work to do, but Saturday's win over Michigan State gave them a sweep of the Spartans, a .500 record in the Big Ten and at least a fighting chance of earning a bid if they beat Illinois in the 4/5 game of the conference tourney. Only if they win two games in Chicago, though -- and that would require an upset of Ohio State -- are they a lock.

• Alabama. The Crimson Tide are shaping up to be the most curious bubble case -- they're 12-4 in the SEC after beating Georgia on Saturday, but their RPI is in the high 80s and their out-of-league résumé is so laughable that the best win is over Lipscomb. Will the committee really exclude the team with the second-best record in a power conference?

4. At 30-4 and 19-1 in the Atlantic Sun, Belmont has done enough to earn a 13 seed -- rather than the 15 or 16 its league winner typically gets in the NCAAs. If the Bruins are properly seeded, they'll be by far the best upset pick in the 4/13 games.

Take a look at Belmont's efficiency, adjusted for competition, in the context of five other candidates for 13 seeds from current bracket projections (data from kenpom.com):

None of the other potential 13s are even close. Belmont's efficiency margin ranks 24th nationally, thanks to a decent offense and a stifling, high-turnover-percentage D. Now, consider Belmont in the context of potential four seeds' efficiency profiles:

Belmont is actually more efficient than St. John's and even with UConn, which means Vegas might consider favoring the Bruins on a neutral court. Considering that these margins are per 100 possessions, and the average game is in the 60s, Belmont is theoretically within one possession of Syracuse, UNC, Louisville and Florida as well. The Bruins wouldn't need a massive stroke of luck to upset those teams -- they'd just need one or two more shots to fall than normal.