With the calendar nearing March, the college basketball season is starting to heat up with just two weeks left in the regular season before major conference tournaments begin.

While teams that are securely in the field don't have much to worry about as far as playing in the NCAA tournament, it's make-or-break time for their seeding line. The difference between a No. 4 or No. 5 seed could be the difference in suffering a first-round bracket-buster. And even the difference between No. 1 seeds matters for earning the best pathway to the Final Four.

Baylor entered Saturday as the projected top overall No. 1 seed, and will close the day as the second No. 1 seed as Kansas vaulted ahead thanks to a thrilling 64-61 win in a battle between two national title contenders. And San Diego State entered the day as a projected No. 1 seed but could potentially fall to the No. 2 line after losing its first game of the season to .500 team UNLV.

Here's a look at the biggest winners and losers among NCAA tournament-secure teams in Saturday's action:

WINNERS

Dayton: After tailing 38-36 at the half to Duquesne, the Flyers (25-2) turned it up a notch in the second half to pull away for an 80-70 home win. National player of the year candidate Obi Toppin finished with 28 points and Dayton's depth continues to be a major strength. Dayton hasn't lost since December and currently holds a No. 2 seed in USA TODAY Sports' latest bracketology. It could be tough for coach Anthony Grant's team to vault to the No. 1 line, but if other teams falter it's certainly a possibility.

BUBBLE WATCH:Which teams damaged tournament hopes, bolstered credentials?

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Louisville: The Cardinals (23-5) took care of business in dispatching a reeling North Carolina team in dominant form, and it's a good thing because teams like UNC (ones that underachieved and are win-hungry) can be the most dangerous because of their ability to stain profiles. Louisville cruised and remains out front in the ACC standings. This outcome also means coach Chris Mack's team is one step closer to bumping up from the No. 4 seed line to No. 3 in the projected bracket.

Duke: After suffering a blowout to North Carolina State earlier this week, the Blue Devils (23-4) needed to rebound. They did that in convincing fashion with an 88-64 beatdown of Virginia Tech at home behind freshman Cassius Stanley's 21 points. A projected No. 2 seed, Duke only has one more chance of acquiring a Quadrant 1 victory (on the road Feb. 29 vs. Virginia) so rekindling a winning momentum was a must.

Virginia: The Cavaliers aren't completely safe yet from the NCAA tournament bubble, but they've drifted pretty far away from it in February thanks to winning seven of their last eight. Saturday's 59-56 win over Pittsburgh on the road was UVA's fourth win in a row and a sign that the reigning national champs are starting to hit their stride as March rolls around. Remember, there are still carry-overs from last year's title team in Mamadi Diakite and Kihei Clark. Tony Bennett's team, always a lockdown defensive unit, could be dangerous in March.

Texas Tech: The Red Raiders (18-9) hammered Iowa State 87-57 to continue its late-season push up the projected bracket. Once a bubble team, Texas Tech has climbed to a No. 8 seed and is positioned to vault to the No. 7 seed line if it keeps winning. TTU has won five of six and has dates with projected No. 1 seeds and Big 12 kingpins Baylor (March 2) and Kansas (March 7) to close out the regular season.

Auburn: The Tigers (23-4) are currently holding a No. 4 seed and could've slipped to the No. 5 seed line had it lost to Tennessee. But after trailing for portions of the game, Bruce Pearl's group took care of business to pull out a 73-66 victory on its home floor.

LOSERS

San Diego State: There had been only 19 teams to ever enter the NCAA tournament undefeated in college basketball history. The Aztecs appeared to be poised to join that club until Saturday's colossal 66-63 upset to UNLV. SDSU stormed back after tailing by double-digits with four minutes left, but ultimately the hole was too big. While it is only one loss, San Diego State could still be in jeopardy of losing out on an NCAA tournament No. 1 seed now since the setback qualified as a Quadrant 3 (home games against opponents ranked 76-160 in NCAA's NET rating) loss to go on the tourney profile.

Gonzaga: Unlike San Diego State's loss to UNLV — a Quadrant 3 home loss — Gonzaga fell to a top-30 opponent on the road, so this outcome won't stain the resume much at all. It does, however, pave room for projected No. 2 seeds Maryland, Duke, Dayton and Florida State to make a late push to vault ahead of both SDSU and Gonzaga for the remaining No. 1 seeds that both Kansas and Baylor should inevitably secure come Selection Sunday.

West Virginia: The Mountaineers (19-8) suffered a setback on the road, losing to TCU 67-60 in overtime, and while they'll still likely hold a No. 4 seed on the projected bracket, Saturday's outcome pushed them further away from the No. 3 line. WVU has now lost four of their last five, and granted two of those losses came against Baylor and Kansas, but the Big 12 slate isn't getting any easier — with two of the last four on the road and a home clash with Baylor on March 7.

Baylor: The Bears are still a national title favorite after Saturday's 64-61 home loss to Kansas. But the setback, which snapped a 23-game winning streak, means the Bears lost their grip on the Big 12 standings (KU is now tied) and also their grip on the top overall NCAA tournament seed. Baylor might need to face the Jayhawks again and defeat them to prove to the committee it's the top team on the bracket.

MORE:Kansas makes its case as tournament's top seed with road win over Baylor

Arizona: After losing in overtime to Oregon on a last-second jumper earlier in the season, it was a dose of deja vu for the Wildcats on Saturday, as they lost 73-72 on another last-second bucket in overtime. The Ducks' Payton Pritchard had 38 points and this outcome likely pushes Arizona from a projected tourney No. 6 seed to a No. 7. It also removed the Wildcats from first place contention in the crowded Pac-12.

Xavier: The Musketeers (17-10) had won four of five to improve to the No. 9 seed line in recent weeks, so Saturday's 64-55 home loss to Villanova won't hurt the team's profile much. But it was a missed opportunity to add a Quadrant 1 victory to the résumé with only three signature wins. Still, Xavier is in good shape being far enough away from the bubble with a top-40 NET score, top-10 strength of schedule and no bad losses.

Colorado: The Buffaloes (21-7) currently hold a No. 5 seed in the latest bracket projection, but might dip closer to the No. 6 line after a 70-63 home loss to non-tourney team UCLA. The loss also pushes Colorado out of first place in the crowded Pac-12 standings. Still, the Buffs have six Quad 1 wins and no bad losses, so they're well positioned to notch a solid seed in the NCAAs.

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Follow college basketball reporter Scott Gleeson on Twitter @ScottMGleeson.