We could see some Carolina blue confetti drop from the ceiling in early April. (Troy Taormina-USA TODAY Sports)

The brackets are set but not all roads to the Final Four are paved evenly. Some paths appear treacherous, while others should provide smooth sailing.

In theory, the top seeded teams are rewarded for their spectacular seasons while lower seeds should need to fight tooth and nail to get past the first round. But even top seeds could struggle given the obstacles placed in their way by the selection committee, especially those in the East bracket.

According to Jeff Sagarin’s Predictor metric, one of the best indicators of future wins this season, the East is the region with the stiffest competition. Teams in this part of the bracket averaged an 83.9 rating during the regular season, roughly equal to a group of teams playing at the level of No. 5 Minnesota.

The toughest road for No.1 Villanova, a path that involves beating the highest-rated Sagarin team in each round of their region, includes wins over No. 16 Mount St. Mary’s (67.5), No. 8 Wisconsin (89.5), No. 5 Virginia (91.7) and No. 2 Duke (91.6), who many felt deserved a top seed in the tournament. In fact, the Blue Devils, even if they faced the most-difficult opponents in their side of the region, would have an almost equal chance, statistically, to reach the Final Four as would top-seeded Villanova.

The Midwest, like the East, also has all three top seeds in the mix for a Final Four run. No. 1 Kansas has a similar chance (18.6 percent) to No. 2 Louisville (18.3 percent) with No. 3 Oregon, considered by some to be a vulnerable top seed after losing Chris Boucher to a torn anterior cruciate ligament, with a 12.4 percent probability of a Final Four appearance. That percentage includes a healthy Boucher, however. So adjust accordingly.

The South region is this year’s easiest, with the average team in that bracket similar to No. 9 Virginia Tech  (82.6). That’s good news for the Tar Heels, who should have an easy time getting to the Final Four. The hardest path for No. 1 North Carolina has victories over No. 16 Texas Southern (68.2), No. 8 Arkansas (83.6), No. 4 Butler (87.1), and No. 2 Kentucky (92.5).

Gonzaga has an easy road to the Final Four, but it is No. 3 Florida State, and not No. 2 Arizona, with the next easiest path in this region.

Arizona has obstacles at every step on their way to the Sweet 16, including Round 1. No. 15 North Dakota sports an effective field goal percentage of 53.4 percent with a 38.4 percent success rate from beyond the arc. And senior Quinton Hooker and sophomore Geno Crandall lead one of the best transition teams in the country, scoring over half the time on the break.

If Arizona survives its first-round matchup, there is either No. 7 St. Mary’s, a team outscoring opponents by plus-24.6 points per 100 possession after adjusting for strength of schedule, or No. 10 VCU, a potential Cinderella team, waiting in the round of 32.

Florida State, meanwhile, matches up with Florida Gulf Coast first, then whoever emerges from the No. 6 Maryland/No. 11 Xavier game. If Maryland wins, Florida State is facing the tournament’s most over-seeded team. If Xavier wins, the Seminoles go up against one of the worst three-point shooting teams in the country (34 percent), a skill that is often a prerequisite to success for an upset pick.

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