It's Championship Week in college basketball and while some teams are pretty much assured a berth in the upcoming NCAA Men's Division I Basketball Championship tournament, aka March Madness, some are making a last-ditch effort.

Besides the Super Bowl, March Madness is one of the most popular sports betting events and even though Selection Sunday takes place about three days from now, here are some teams to keep an eye on.

North Carolina Tar Heels

In the latest college basketball rankings of the season, which came out earlier this week, UNC was the consensus No. 1 team—top ranked in both the Associated Press and ESPN/USA Today polls—but they haven't been too sharp for bettors.

Despite owning a 27-3 record coming into the week, the Tar Heels haven't been nearly as good as a bet, going 12-17 ATS this season.

Also, one of its key players is nursing a toe injury. Last year's ACC player of year, Tyler Hansbrough, is playing well but this year's POY Ty Lawson is not.

Lawson is nursing a toe injury and missed UNC's game against Virginia Tech, a game that the Tar Heels won 79-76, but also one they failed to cover on as 13-point faves.

Louisville Cardinals

Ranked fifth in both polls this week, the Louisville Cardinals aren't far behind the North Carolina Tar Heels with a 26-5 record but of more importance to bettors Louisville is superior when it comes to betting, with an ATS record of 19-12.

On top of that, the Cards are one of the hottest teams going into March Madness, winning nine games in a row (9-0 SU) and going 7-2 ATS.

Siena Saints

Siena defeated Niagara 77-70 in the Metro Atlantic Athletic Conference championship game, as a 3.5-point fave, to capture a March Madness berth.

Siena had a very good season, going 26-7 SU but was below average in betting numbers with a 15-16 ATS record.

Fortunately, a team doesn't advance based on its ATS record and the Saints are 17-3 SU in its last 20 games. Could Siena be this year's Cinderella team?

Memphis Tigers

All that stands between Memphis and a Conference USA tourney title is Tulsa and the two will play tomorrow; the Tigers are 29-3 SU and have been profitable at 18-11-2.

The Tigers are also in the midst of an incredible winning streak, having not lost in 24 games (24-0). Will they keep it up in the tournament? Memphis was runner-up in last year's tourney.