March Madness: Who is on the bubble this week ahead of Selection Sunday?

The last batch of men’s conference tournaments get underway this week, which means teams right on the bubble are running out of time to prove they belong in the NCAA tournament.

Here’s a look at the biggest bubble teams who need to make a run this week before Selection Sunday.

North Carolina: Tar Heels desperately need a run

After making it to the national championship game last April, and entering this season ranked No. 1, North Carolina has struggled.

Now, headed into the ACC tournament, the Tar Heels are perhaps the most surprising team sitting right on the bubble.

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North Carolina finished the regular season with a 19-12 record, which was good enough for seventh in the ACC standings. The Tar Heels ended the season having won three of their last four, but that came right after a stretch where they lost five of six. They beat just two ranked teams all year, one of those a win over then-No. 6 Virginia late last month.

They fell to Duke, 62-57, to close out the regular season on Saturday night, which gave the Blue Devils the double-bye in the ACC tournament. North Carolina will open the tournament on Wednesday against either Boston College or Louisville.

The Tar Heels have to have a big showing in Greensboro this week. If they get knocked out early, especially in the first round, they may miss out on earning a bid to the NCAA tournament and be bound for the NIT — something that would have sounded ridiculous back in November.

The bottom half of the Big 12

There’s little question that the Big 12 is the strongest conference in college basketball this season.

What’s up for debate now, however, is how many teams will make it into the NCAA tournament.

Outside of the top half of the conference — meaning Kansas, Kansas State, Texas, Baylor and TCU — four other Big 12 teams are still vying for at-large bids. That’s 90% of the conference with potential to make it.

First, let’s start with Iowa State. The Cyclones are likely in the tournament regardless of how the Big 12 tournament plays out, but things haven’t been going well in Ames in recent weeks. After making it as high as No. 11 in the poll, Iowa State ended its season having lost eight of its last 11 games. The lone bright spot in that stretch came with a 15-point win over Baylor, which came only after the Cyclones cut guard Caleb Grill from the team. An opening-round loss in Kansas City won’t doom the Cyclones, but it will result in them drawing a tough seed on Selection Sunday.

Oklahoma State looked like it was right in the mix for an at-large bid, too, but the Cowboys dropped five of their last six to end the regular season. They’ll need at least one win in the conference tournament, if not several, to avoid an NIT appearance.

West Virginia and Texas Tech are in similar positions, though the Mountaineers are a step ahead with several notable wins on their resume. And Texas Tech coach Mark Adams was suspended on Sunday, which doesn’t help the Red Raiders any. Regardless, both West Virginia and Texas Tech must to advance to at least Friday in Kansas City to ensure they make it to the NCAA tournament.

Arizona State: Buzzer-beater gave Sun Devils new life

Arizona State hasn’t been perfect this season. In fact, the Sun Devils have several bad losses on their resume.

But, as shown by Desmond Cambridge’s incredible buzzer beater last month, the Sun Devils may be just lucky enough when it matters most.

Cambridge stunned No. 7 Arizona last month with a wild half-court buzzer beater to pick up their 20th, and by far the biggest, win of the season. Unfortunately for the Sun Devils, they backed that up with losses to UCLA and USC to end the season — which kept them right outside of the NCAA tournament field on the bubble.

Arizona State will open the Pac-12 tournament against Oregon State on Wednesday. A win there, and then again in the second round against USC on Thursday may be what the Sun Devils need to sneak into the NCAA tournament. If things go right, there’s no reason why they can’t pull off a great upset or two in the coming weeks.

Wisconsin, Michigan, Penn State scrambling in Chicago

The Big Ten tournament has several teams right on the bubble, which should make this weekend extremely entertaining in Chicago.

Wisconsin, despite having the worst seed in this group, is probably in the best position to get in — though an opening-round loss to Ohio State on Wednesday could change that quickly. The Badgers also ended the year having lost three of their last five, and haven’t won back-to-back games since early January.

Penn State isn’t far behind them, especially after seeing how the Nittany Lions closed out the year. They rallied back and beat Maryland at the buzzer on Sunday, which marked their fifth win in six games. A third win this season over Illinois would go a long way in ensuring they make the tournament.

Michigan's at-large hopes took a big hit with a pair of overtime losses to Illinois and Indiana to end its regular season. The Wolverines will start the Big Ten tournament with a matchup against Rutgers, which is a must-win game — especially seeing that top-seeded Purdue is awaiting the winner. Michigan may need to pull some big upsets this week to sneak into the NCAA field.