When Dan Monson coached Gonzaga to an improbable Cinderella run to the Elite Eight in 1999, it was among the most shocking tournament developments in college basketball history.

Yes, John Stockton played in Spokane, but the Bulldogs never made an NCAA Tournament until 1995. There was no reason to believe that they'd become a regular in the Big Dance -- let alone, essentially, a power conference program playing in a mid-major conference. That's exactly what they've done, as Mark Few built off what Monson began and has guided Gonzaga to an 18-year NCAA Tournament streak that's about to become 19.

The Zags are undefeated at 26-0, and they have been ranked first in the AP top 25 each of the past three weeks. They beat Florida, Iowa State, Arizona, Washington and Tennessee in nonconference play, and now they own a season sweep of Saint Mary's, a top-25 West Coast Conference rival, after winning on the road against the Gaels on Saturday.

Gonzaga is still searching for its first-ever Final Four bid, but this year's team appears to have as good of a chance as any, with a talented lineup led by guard Nigel Williams-Goss and center Przemek Karnowski. The WCC isn't deep, but the Zags have been dominant, winning 18 straight games by at least 10 points.

Gonzaga has reached the remarkable point where the Final Four, and even winning the national championship, is a legitimate hope. This team is good enough to do it. Of course, by reaching No. 1 in the polls, Gonzaga has already earned a rare place in history. Not surprisingly, teams from the Power Five conferences -- plus those who have been in the Big East -- have dominated the rankings over the years, particularly since the 1970s began.

So what kind of company does Gonzaga have? With the help of the poll data compiled by Sports-Reference and College Poll Archive, let's break down the non-power-conference teams that have reached No. 1 in the AP poll in the regular season and what they accomplished after doing so.

There are many tiers of conferences -- the Mountain West, Atlantic 10 and West Coast are miles ahead of the Southland and America East, for example -- but for the purposes of this article, we're exploring teams that aren't currently in Power Five conferences (ACC, Big Ten, Big 12, Pac-12, SEC) and haven't been part of the Big East (Connecticut, DePaul, Cincinnati).

Pre-1970 Teams

Prior to UCLA's complete dominance in college basketball under John Wooden in the late 1960s and early '70s, there was substantial parity in the sport. UTEP (then Texas Western), Loyola (Chicago), San Francisco and La Salle were among the teams that were ranked No. 1 and won national championships. The AP basketball poll started in 1949, and between then and 1970, the following teams reached the top of the rankings during the regular season: Wichita State (1965), San Francisco (1955, 1956), Bradley (1950, 1951), Houston (1968), Saint Louis (1949), La Salle (1953, 1955) Duquesne (1954), Holy Cross (1950) and Loyola (1964). The sport has changed drastically since then, and UNLV is the only team since 1966 Texas Western to win a national championship that hasn't become a member of a Power Five conference or the Big East.

Gonzaga

2013: 1 seed, lost second round. The Zags reached as high as No. 3 in the Adam Morrison era, but they didn't ascend to the top of the AP poll until 2013, when they earned a No. 1 seed for the first time in their 15th straight NCAA Tournament appearance. Led by Kelly Olynyk, Gonzaga lost regular-season games to Illinois and Butler but went undefeated in West Coast play and move to No. 1 in the top 25 at the end of the regular season. In the tournament, however, the Bulldogs disappointed, as they were chased out by Final Four-bound No. 8 seed Wichita State in the Round of 32. The Zags made it to the Elite Eight in 2015 and the Sweet 16 last year.

Houston

1983: 1 seed, lost national final. Perhaps Houston shouldn't be included, as its biggest run of success came as a member of the Southwest Conference, which was a major conference before folding. Of course, the Southwest was more known for its football prowess, and Houston has made one NCAA Tournament in the past 25 years as a member of Conference USA and the AAC. Back in its Southwest heyday, Houston enjoyed plenty of success under coach Guy Lewis, rising to No. 1 in 1967-68 with back-to-back national semifinal losses. Since 1970, its one No. 1 ranked team succumbed to one of the biggest upsets in one of the best games ever. The Phi Slama Jama team led by Hakeem Olajuwon, Clyde Drexler and Michael Young started the 1982-83 campaign ranked 14th after losing in the previous Final Four. The Cougars lost early games to Syracuse and Virginia, then went on a tear, winning 22 straight entering the NCAA Tournament to capture a No. 1 seed. They rolled to the final, only to lose to Jim Valvano's N.C. State squad on Lorenzo Charles' dunk at the buzzer. The next year, Houston hovered around the top five and lost the national championship game to Georgetown.

Indiana State

1979: 1 seed, lost national final. Two Sycamores teams have ever been ranked. Not surprisingly, they both featured Larry Bird. The 1978 team missed the NCAA Tournament, but the next season, Bird averaged 28.6 points per game and led them to a perfect record all the way through Missouri Valley Conference play, allowing them to make an improbable rise to the top of the AP poll. They advanced to the national final in their first-ever tournament appearance, but their perfect run came to an end against Magic Johnson and Michigan State in one of the most famous championship games ever. The Spartans won 75-64, Bird went to the NBA and Indiana State has gone to the NCAA Tournament only three times since then.

Massachusetts

1995: 2 seed, lost regional final. When John Calipari took over the Minutemen in 1988, they hadn't finished a season with a winning record in over a decade. They had also never appeared in an AP poll. It didn't take long for that to change. After three straight trips to the NCAA Tournament, UMass rose to No. 1 in the 1994-95 season, ultimately going 13-3 in the Atlantic 10. Centered around the frontcourt combination of Lou Roe and Marcus Camby, the Minutemen earned a No. 2 seed and lost in the Elite Eight to Oklahoma State.

1996: 1 seed, lost Final Four. Camby became national player of the year as a junior, and UMass spent much of the year ranked No. 1 after racking up big win after big win in nonconference play -- including one against preseason No. 1 Kentucky in its season opener. The Minutemen's only loss was against George Washington late in the conference season. They made the Final Four, only to lose 81-74 in a rematch with eventual national champion Kentucky in the semifinals. Afterward, the Final Four appearance was vacated because Camby accepted gifts from an agent.

Memphis

1983: 4 seed, lost regional semifinal. The Tigers had never been ranked higher than 10th in the AP poll until Dana Kirk was hired. In his fourth season, as part of a mishmash of teams in the Metropolitan, Memphis opened the year ranked sixth and rose to No. 1 after an 11-0 start but stumbled in the second half. It was chased out of the tournament by top seed Houston. Memphis later had to vacate its NCAA Tournament appearances in this era because of recruiting violations, and Kirk spent four months in prison after being convicted of obstruction of justice and tax evasion.

2008: 1 seed, lost national final. Memphis vacated its 1985 Final Four appearance, then had to do the same in 2008 because of violations involving Derrick Rose. After losing only once in the regular season and spending all year in the top three of the AP poll, Rose and Calipari led the Tigers all the way to the national championship, where they lost 75-68 in overtime to Kansas after the Jayhawks' Mario Chalmers hit a 3-pointer at the end of regulation.

Saint Joseph's

2004: 1 seed, lost regional final. The Hawks were a perfect 27-0 in the regular season, only to go one-and-done in the Atlantic 10 tournament thanks to a loss to Xavier. They were a No. 1 seed anyway, led by Jameer Nelson and Delonte West, and they made it to the Elite Eight, where they lost to Oklahoma State on a John Lucas 3-pointer in the final seconds.

San Francisco

1977: lost first round. The Dons were a national power in the 1950s thanks to the presence of Bill Russell, who led them to back-to-back national championships. Twenty years later, they returned to the top of the AP poll with a high-scoring lineup led by Bill Cartwright. They won the West Coast Athletic Conference with a perfect record and won their first 26 games. They lost their regular-season finale at Notre Dame, then went one-and-done in the NCAA Tournament in a 121-95 loss to UNLV.

Temple

1988: 1 seed, lost regional final. An Atlantic 10 power under John Chaney, Temple never made a Final Four under him, going 0-5 in the Elite Eight -- a run that brings to mind Gonzaga's recent success. Of course, Temple's status as a big school in Philadelphia makes its long-term success easier to believe than Gonzaga's. In 1987-88, the Owls lost only one regular-season game, by one point at UNLV, and they fell short against Duke, a No. 2 seed, in an NCAA Tournament regional final.

UNLV

1983: 3 seed, lost second round. Six years after a Final Four run, Jerry Tarkanian led the Runnin' Rebels to the top of the AP poll in a season that also saw Houston and Memphis claim the No. 1 spot at various points. UNLV started the season 24-0 before losing back-to-back games to West Virginia and Cal State Fullerton. UNLV proceeded to lose to N.C. State in its first tournament game -- the Wolfpack team that went on to one of the most stunning national titles ever.

1987: 1 seed, lost Final Four. UNLV spent most of the 1986-87 season ranked No. 1, going undefeated in the Pacific Coast Athletic Association but losing a midseason game to Oklahoma by a point. The Rebels cruised to the Final Four, where they lost to national champion Indiana in the semifinals.

1990: 1 seed, won national championship. UNLV reached its zenith under Tarkanian to kick off the 1990s. It actually began the season ranked No. 1, but early losses to Kansas and Oklahoma set it back. After falling, the Rebels were ranked second by the end of the regular season and earned a No. 1 seed, eventually demolishing Duke 103-73 in the final behind Anderson Hunt and Larry Johnson. Playing out of the Big West, they remain the last non-power conference team to win a title.

1991: 1 seed, lost Final Four. After winning the title, UNLV was a wire-to-wire No. 1 in the AP poll that finished the regular season undefeated. The streak was ended in a revenge game: Duke beat the Rebels 79-77 in the semifinals. Tarkanian resigned a year later amid NCAA troubles, and UNLV hasn't advanced beyond the Sweet 16 since then.

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