The Gaels, at 28-5, with a 16-2 mark in the West Coast Conference, holding a road win over Gonzaga and two victories against BYU, were passed over for the NCAAs despite holding on to the No. 25 spot in the AP poll after the regular season.
Instead, Saint Mary's will compete in its sixth NIT tournament in school history, opening as a No. 1 seed against No. 8 seed Southeastern Louisiana (22-11) on Tuesday night. The Gaels, who are 5-5 all-time in the NIT, competed in the postseason event in 2009, 2011, 2014, 2015 and 2016.
This marks the program's 11th consecutive postseason appearance under coach Randy Bennett, although a few of those NIT appearances came after similar snubs from the NCAA.
The problem, according to the committee, is strength of schedule, particularly in the non-conference season. Bennett would counter with the difficulty of scheduling power conference teams for home-and-home series.
And then there was the new quadrant system used by the committee this season to evaluate strength of schedule. Saint Mary's simply didn't have enough opportunities in the first quadrant.
"Explain to me how the quadrant system is scored," Bennett told ESPN. "There's the problem."
The Gaels are 5-2 all-time in the NIT at home. If they win Tuesday in Moraga, Calif., they advance to play the winner of No. 4 seed Boise State vs. No. 5 Washington.
Saint Mary's is led by one of the top players in the country -- center Jock Landale, who was selected as a second-team All-American on Monday by the United States Basketball Writers' Association of America. The senior is averaging 21.4 points and 10.3 rebounds, shooting 64 percent from the field.
Three other Gaels average double-figure points, including senior forward Calvin Hermanson at 11.0 per game; he is second in school history with 242 career 3-pointers. Senior guard Emmett Naar is the school's career leader in assists, with 791, averaging 8.0 per game this season, second in the country.
Southeastern Louisiana was 15-4 in the Southland Conference, sharing the regular season title with Nicholls State. The Lions missed out on an automatic bid to the NCAA Tournament, falling to Stephen F. Austin 59-55 in the conference tournament title game.
"It's disappointing," coach Jay Ladner after the title-game loss. "I thought our guys played hard. I'm very proud of them. We had won nine in a row up to this point. We'll regroup and get ready to play in the NIT."
Senior forward Jordan Capps averages 13.2 points per game; 5-foot-9 point guard Marlain Veal scores 13.1 points per game and averages 6.1 assists.
This will be the first NIT appearance for the Lions, who have made a school single-season record 249 3-pointers, making 36.0 percent of their attempts. One thing to watch in the NIT is experimental rules that include pushing the 3-point line back 20 inches (not as much in the corners) to match the distance in FIBA play.
Also, the lane will be widened to 16 feet, rather than 12.
Those changes could create more space in the lane for the 6-foot-11 Landale. The Lions don't have a player taller than 6-8.
Landale said the Gaels have to convert the NCAA snub into NIT fuel.
"We all expected to make it," Landale told the San Francisco Chronicle. "We thought we were an upset waiting to happen (in the NCAAs). Now we just have to prove a point."