Roy Williams/AP

THE MOST IMPORTANT THING WE LEARNED LAST WEEK

That North Carolina -- a team that prior to Sunday hadn't allowed an opponent to get within 15 points -- is vincible. The fact that the Tar Heels were beaten on their home floor by Boston College, which may not even make the NCAA tournament, offers hope to the second tier of national title contenders. If Tyler Hansbrough clangs as many close-rangers in Detroit as he did against the Eagles, or if Tywon Lawson is more reckless than efficient, as was the case in a head-to-head battle with BC's Tyrese Rice, then UNC might actually be vulnerable.

Now seems as good a time as any to rate the Tar Heels' five most viable challengers for the 'chip, based both on observations and gut feelings. These aren't Power Rankings (those are back on Thursday after a holiday hiatus) but rather who I think has the best odds of being matched up against UNC on the season's final Monday night -- as well as optimistic/pessimistic views of how they might fare against the overwhelming title favorites.

1. Pittsburgh

Optimistic View: The DeJuan Blair-and-Tyrell Biggs duo could go blow-for-blow with Hansbrough and Deon Thompson in the post, and Levance Fields is the nation's only floor general with a steadier hand than Lawson. Last year's Panthers wouldn't have been able to defend Carolina's offense, but this year's Pitt D has been ratcheted up to an elite level, ranking seventh in adjusted defensive efficiency, 13 spots ahead of UNC.

Pessimistic View: Speed isn't Fields' strong point, and Lawson is the fastest end-to-end point guard in the country. The perimeter length of Danny Green and Marcus Ginyard might be able to bother Sam Young, whom most opponents struggle mightily to defend. Pitt also doesn't have the quality depth to match Carolina's.

2. UConn

Optimistic View: Hasheem Thabeet has an uncoachable trait -- supreme length, at 7-foot-3 -- that could bother Hansbrough more than the brute-force assaults he usually sees. The Huskies fit the "NBA formula" for title teams, possessing the highest number of future pros of any team not named North Carolina. They can also go eight deep without much of a drop-off, pulling Stanley Robinson, Kemba Walker and Gavin Edwards off the bench.

Pessimistic View: Most of the players on UConn's roster have yet to be a part of a single NCAA tournament victory; can they realistically be expected to win a title with such limited March Madness experience? Thabeet also seems to shrink in big games; his impact against Gonzaga and Georgetown in December was extremely limited.

3. Michigan State

Optimistic View: The Spartans sunk in the polls after a couple of bad early losses (to Maryland and UNC), but they're a much different team with Goran Suton on the floor, and they match up athletically with the Heels. Kalin Lucas actually has a better assist-to-turnover ratio than Lawson does -- as well as the speed to keep up with the Heels' whirling dervish.

Pessimistic View: When Carolina blows you off the floor by a 35-point margin earlier in the year -- in front of a green-tinted crowd at Ford Field -- it's a sign that you have no chance of beating them later in the season. The addition of Suton isn't enough to change that.

4. Wake Forest

Optimistic View: Jeff Teague, who might be the season's biggest breakout story, is a more lethal scorer than anyone in UNC's backcourt. The Deacs have three legitimate NBA players in their starting lineup (Teague, James Johnson and Al-Farouq Aminu) and far more "effective height" in their frontcourt than the Heels do. Wake is already a better defensive team than Carolina, and when the Deacs freshmen -- especially Aminu -- fully blossom on offense, they'll really be dangerous.

Pessimistic View: This is a team with no NCAA tournament experience that might need to wait a year before being considered a real national-title contender. Wake has the talent right now, but in terms of veteran savvy, it lags well behind Carolina.

5. Louisville

Optimistic View: The Cards, in their current condition, have no shot at winning a national title. Their offense is mediocre and guards Edgar Sosa (prior to Sunday's win over Kentucky) and Andre McGee are playing well below their potential. So why are they here? Because the frontcourt of Samardo Samuels, Earl Clark and Terrence Williams is still better than Carolina's; their defense is better than Carolina's; and if their backcourt can get up to speed late in the season, it's not hard to imagine the 'Ville making a sleeper run to Detroit as a five-seed.

Pessimistic View: Louisville's offense simply can't click without David Padgett's understated wizardry in the middle. He was the Cards' smartest and most efficient player, and without him (he graduated), they don't score like an elite team. Carolina will overwhelm them in a high-possession game.

The next five: Duke, Georgetown, Gonzaga, Oklahoma, UCLA

SI.COM'S STARTING FIVE

(Wearing Indiana State's "I-For-Indiana" powder blues, which they rocked against Evansville on Sunday. Next, I'd like to see Tennessee-Martin use an outline of the Volunteer State as its hyphen ...)

1. Antonio Anderson, G, Memphis: Anderson, a lover of the "China people," posted the first triple-double by a Tiger in 16 years with a 12-point, 10-rebound, 13-assist (and zero turnover!) line in a win over Lamar on Saturday.

2. Lester Hudson, SG, Tennessee-Martin: He scored 41 points -- and grabbed 10 boards -- in a win over Central Arkansas on New Year's Eve, and remains the only player on the NCAA scoring leaderboard to have hit the 20-point mark in every game this season.

3. DeJuan Blair, PF, Pitt: Blair grabbed only six fewer boards (17) than the entire Georgetown team did in Saturday's 70-54 win over the Hoyas. He also scored a team-high 20 points.

4. Michael Washington, PF, Arkansas: The former backup, an All-Breakout Team candidate, double-doubled against Oklahoma (24 points, 11 boards on Dec. 30) and North Texas (34 points, 11 boards on Jan. 3).

5. John Bryant, C, Santa Clara: If you somehow missed college hoops' premier preseason event -- the Cable Car Classic -- you missed Bryant scoring 33 points and pulling down 17 boards in an overtime win over UTEP.

MY ONE WISH ...

That the Oregon Pit Crew's Lebron-Chalk Experiment hadn't backfired so badly before Sunday's loss to UCLA. It wasn't a bad idea -- according to the FSN broadcast, the Ducks' student section did King James' signature pregame move, throwing chalk up into the air prior to tip-off -- but instead of creating a great visual, the substance just got all over the court and a team towel boys had to be summoned to wipe it up. This awkwardly delayed the start of the game ... and put chalking in serious jeopardy as a UO pregame tradition.

THE ONE GAME YOU SHOULD CARE ABOUT

Monday, Jan. 5: Georgetown at Notre Dame, 7 p.m.

The longest home winning streak in Division I is looking somewhat fragile after what transpired at Madison Square Garden this weekend: The Irish lost to St. John's, which is not easy to do. Unless they come hungry against Georgetown, the 43-game run at the Joyce Center could be over.

YOUR MONDAY MOMENT OF ZEN

A ridiculous parody of old-timey hoops, set to the Beastie Boys instrumental Sabrosa, starring a mulletted Robbie Cowgill and the '07-08 Washington State Cougars? Can you get more Zen than this?