Being the last undefeated team in college basketball doesn't guarantee you a national championship. It also doesn't prevent it from happening. In fact, holding the only bagel in the loss column is normally a positive omen for March. 

How do we know? 

I've done the research to prove it. San Diego State is 21-0 after winning Sunday at UNLV, the best start in program history. SDSU has already set records this season in these respects: it's the first time SDSU has been the last unbeaten in college basketball, and it's the first time a Mountain West team has been the last team without a loss. 

Somewhat ironically, SDSU has not yet held the No. 1 spot in the AP Top 25 rankings. (It's No. 3 in the latest poll.) If it keeps up the winning, that could happen though, and if SDSU is the next new team to hold the No. 1 spot, it will set the record by becoming the eighth different school in one season to be No. 1. The AP poll dates back to 1948 and has never had more than seven in a season.

The Aztecs will get to at least Jan. 29 before it can be defeated, meaning the only team since 2015 to get deeper into the season before taking a loss was 2016-17 Gonzaga, which fell at home in its regular-season finale to BYU

Let's get to the evidence. These are the fates of every team that was the last to lose on a given day since 1992. If more than one team lost on the same day, they are accounted for. 

YearTeamFirst loss
(Record before L)
Lost toFinal RecordNCAAT outcome
1991-92DUKEFeb. 5 (17-0)@ UNC34-2Won title
1991-92OKLAHOMA STATEFeb. 5 (18-0)@ Nebraska28-8Sweet 16
1992-93VIRGINIAJan. 20 (11-0)@ UNC21-10Sweet 16
1993-94UCLAJan. 30 (14-0)@ California21-7First round
1994-95UCONNJan. 30 (14-0)@ Kansas28-5Elite Eight
1995-96UMASSFeb. 24 (26-0)vs. George Washington35-2Final Four
1996-97KANSASFeb. 4 (22-0)@ Missouri34-2Sweet 16
1997-98UTAHFeb. 1 (18-0)@ New Mexico30-4Title game loser
1998-99UCONNFeb. 1 (19-0)vs. Syracuse34-2Won title
1999-2000SYRACUSEFeb. 7 (19-0)vs. Seton Hall26-6Sweet 16
2000-01STANFORDFeb. 3 (20-0)vs. UCLA31-3Elite Eight
2001-02DUKEJan. 6 (12-0)@ Florida State31-4Sweet 16
2002-03DUKEJan. 18 (12-0)@ Maryland26-7Sweet 16
2003-04SAINT JOSEPH'SMarch 11 (27-0)vs. Xavier (A-10 tourney)30-2Elite Eight
2004-05ILLINOISMarch 6 (29-0)@ Ohio State37-2Title game loser
2005-06FLORIDAJan. 21 (17-0)@ Tennessee33-6Won title
2006-07CLEMSONJan. 13 (17-0)@ Maryland25-11NIT
2007-08MEMPHISFeb. 23 (26-0)vs. Tennessee38-2Title game loser
2008-09WAKE FORESTJan. 21 (16-0)vs. Virginia Tech24-7First round
2009-10KENTUCKYJan. 26 (19-0)@ South Carolina35-3Elite Eight
2010-2011OHIO STATEFeb. 12 (24-0)@ Wisconsin34-3Sweet 16
2011-2012MURRAY STATEFeb. 9 (23-0)vs. Tenn. State31-2Second round
2012-2013MICHIGANJan. 13 (16-0)@ Ohio State31-8Title game loser
2013-14WICHITA STATEMarch 23 (35-0)vs. Kentucky (NCAAT)35-1Second round
2014-15KENTUCKYApril 4 (38-0)vs. Wisconsin (NCAAT)38-1Final Four
2015-16SMUJan. 24 (18-0)@ Temple25-5Ineligible
2016-17GONZAGAFeb. 25 (29-0)vs. BYU37-2Title game loser
2017-18VILLANOVADec. 30 (13-0)@ Butler36-4Won title
2017-18TCUDec. 30 (12-0)vs. Oklahoma21-12First round
2017-18ARIZONA STATEDec. 30 (12-0)@ Arizona20-12First Four
2018-19MICHIGANJan. 19 (17-0)@ Wisconsin30-7Sweet 16
2018-19VIRGINIAJan. 19 (16-0)@ Duke35-3Won title

What we learned

The good news: Five times we've seen the final unbeaten team go on to win the national title, and it's been the case the past two seasons. (In 2018 Villanova took its loss before Arizona State and TCU, but that's a technicality as all those games were played on the same day.)

The teams on the list are eclectic. You've got UMass from a faraway Atlantic 10 era and you've got Memphis back when Conference USA really mattered. Duke's Mike Krzyzewski and John Calipari, who's twice been the last unbeaten and Kentucky and also did it at UMass, appear more than any other coach. Former UConn coach Jim Calhoun is the only other coach with at least two seasons being the last one standing.

Here's what 28 seasons worth of data tell us:

  • First losses come away from the last unbeaten's home venue 70% of the time. San Diego State's toughest remaining games are at New Mexico on Jan. 29, at Boise State on Feb. 16 and season finale at Nevada on Feb. 29. Their chances of going undefeated in the regular season? According to CBS Sports data analyst Stephen Oh, it's hovering just under 1%. 
  • San Diego State is sitting on the average record for the final unbeaten team before taking its first loss. Since 1992, it's a 20-0 mean mark and then the bagel disappears. Omen for Sunday at UNLV? 20-0 also matches 2010-11 San Diego State's start.
  • Here's a great pattern: 11 of the 34 teams to lose last on the latest date (that's 34.4%) have gone on to make the Final Four. SDSU has never made it past the Sweet 16.
  • Only two teams have been the final to lose and not make the NCAA Tournament: Clemson in 2007 and SMU in 2016. Clemson is the only one to fall through the floor, as SMU would have made it if not for sanctions/a postseason ban. 
  • Removing Clemson and SMU from the equation, the average number of NCAA Tournament wins since 1992 for the last teams to lose: 3.1. Only four times did the last team fail to even win one NCAA tourney game. San Diego State's expectation should be the Sweet 16 at the least. The Elite Eight is practical. 
  • The most common exit for the last unbeaten team is the Sweet 16 (eight times). 
  • Average final record for the last unbeaten team: 30-5. It feels like SDSU is going to best that. 
  • We've seen 19 instances in the history of Division I where teams have made it to the NCAA Tournament without a loss. At this stage, historically speaking, SDSU is hovering around a 17% chance that will happen
  • They were all chasing the 1975-76 Indiana Hoosiers, who went 32-0 and are the last team to go undefeated through the NCAA Tournament.

San Diego State's one of the pleasant surprises this season. They rank No. 1 in the NET and No. 1 in Strength of Record. In a year when it's all too common to hear about how nobody's great, we could come to accept and realize that these Aztecs are. Remember these trends come March. History heavily leans that, even if the first weekend is dotted with upsets, SDSU will not be the victim of one.