If there was any doubt about the identity of the 2021 NCAA men's basketball tournament favorite, it evaporated sometime around 3:30 p.m. ET on Monday afternoon. In a March of surprises and upheaval, No. 8 seed Oklahoma wanted in on the upset act. Top-seeded Gonzaga, though, had other plans.
The Zags took Oklahoma's best shot. They cruised to a 16-point win anyway. They still haven't been beaten this season. They still haven't been given a single-digit game since early December.
They are dynamic and experienced, well-rounded and well-schooled, and the clear No. 1 team in men's college hoops.
They will, however, have challengers. Maybe not in the Sweet 16. But certainly in the Elite Eight and beyond. A few candidates emerged on Monday.
And whereas upsets elsewhere have busted regions wide open, upsets in the West region will actually make Gonzaga's road to the Final Four more difficult.
Oregon emerges as a threat
Oregon made its 2021 tournament debut on Monday, some 40 hours later than expected. The Ducks' first-round matchup with VCU was called off. Its second-round showdown with Iowa was highly anticipated, in part because nobody quite knew which version of the Ducks would show up.
It didn't take long, though, to recognize the good version. The free-flowing version. The dangerous version. The one that can give Gonzaga a run.
Oregon ran the high-scoring Hawkeyes out of Bankers Life Fieldhouse with one of the very best performances of March Madness thus far. It spread the floor, with a lineup entirely composed of 6-foot-6 wings, and easily would've topped the century mark if the game hadn't been in hand.
And perhaps just as notably, nothing about the performance was fluky. Nothing about it was unrepeatable in later rounds. Not even against Gonzaga.
USC, which blasted Kansas on Monday, stands in the way of that matchup. But if it materializes, it's a tricky one for the Zags. Much more so than Iowa would have been. The Ducks can score off the bounce. They could hang with the No. 1 overall seed in transition. They could attack Gonzaga center Drew Timme from the perimeter, and expose the Zags' hidden rim-protection woes.
They very well could lose by double-digits, just as every Gonzaga opponent seems to. Heck, they could lose to USC on Sunday. The sixth-seeded Trojans might even be favored. They are now, per KenPom, the sixth-best team in all of college hoops.
Either way, Gonzaga's second weekend got tougher when the second and third seeds in its region fell.
The new strongest region
Down in the East region, meanwhile, there are also potential challengers — the same ones many expected to see on the second weekend all along.
There is Michigan, which weathered a strong LSU storm on Monday night, and surfaced unscathed with an impressive 86-78 victory.
There is Alabama, which rolled past Maryland in the second round, scoring 1.45 points per possession against a very solid Terps defense.
And there is Florida State, which ran into Gonzaga in each of the previous two NCAA tournaments; and which, in seeing off Colorado on Monday, looked more than capable of setting up a Final Four rubber match with the Zags.
With Abilene Christian gone, having been sent home by UCLA, the East region is the closest thing we have to chalk. Its Sweet 16 survivors, as a collective, are the strongest remaining group of the four.
So, while Gonzaga remains transcendent, and a +150 favorite at BetMGM to cut down nets two weeks from now, the latter half of its path to glory could end up as difficult as could possibly be.
Who can beat Gonzaga?
Who, specifically, could take down the Zags?
Yahoo Sports' Jeff Eisenberg effectively answered that question Monday night with his re-ranking of the Sweet 16. Gonzaga's next opponent, Creighton, is ranked 14 of 16. In other words, the Bluejays are no threat.
But after that, the Zags — No. 1 on the list — could have to go through No. 7, No. 3 and No. 2.
There appear to be five teams in all from the left side of the bracket that could keep Gonzaga off the sport's biggest stage in April. In order of upset likelihood — in my opinion, not Jeff's — they are:
Alabama, a defensive juggernaut now finding its uptempo offensive groove.
Oregon, whose March marvelousness is no fluke, and whose upside is remarkably high.
Michigan, which on balance is the third-best team remaining, but which isn't at full-strength. The Wolverines also have the most obstacles between them and Gonzaga.
USC, few have talked about the Trojans as a Final Four threat, but they turned heads with their destruction of Kansas.
Florida State, which may very well be the second-best team on this list, but will have to go through Michigan and 'Bama just to reach Gonzaga.
The Sweet 16 tips off Saturday at 2:40 ET, with the right side of the bracket up first. The left side will have to wait for Sunday. Creighton and Gonzaga will tip off the four-game slate.
In the meantime, the women's tourney progresses to its second round on Tuesday – after a Monday full of drama.
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