A second-round NCAA Tournament matchup between Oregon and UC Irvine is a major surprise, based on their seeds.

But not based on their hot streaks.

The No. 12 Ducks (24-12) have ripped off nine consecutive victories, snatching an automatic bid by winning the Pac-12 tournament and then burying Wisconsin 72-54 with a dominant second half in a first-round game on Friday.

Earlier, the No. 13 Anteaters (31-5) won their 17th consecutive game by upsetting Kansas State 70-64 behind great guard play from Max Hazzard and Evan Leonard, who each scored 19 points.

These teams bring plenty of defense and swagger into Sunday's matchup in the South Region in San Jose, Calif.

"We've got a special group here," said UCI coach Russell Turner. "They're incredibly confident, incredibly competitive."

Said Oregon forward Kenny Wooten: "We're playing so hard right now and together. Our second half is better than our first on defense. We really jump on people."

The Ducks are long and athletic, and their mix of defenses and presses under coach Dana Altman roared to life late in the regular season when he began using a starting lineup featuring four players who are at least 6-foot-9.

Oregon held Wisconsin to 33.3 percent shooting (20 of 60) and is allowing 54.2 points per game during its winning streak.

UC Irvine's defense has been stingy all season. The Anteaters have ample size up front and held Kansas State to 37.3 percent from the field, which was right in line with their defensive season average of 38.0.

Big West champ UCI had early-season wins at Texas A&M and Saint Mary's, and playing a Pac-12 school will likely suit the Anteaters' chip-on-their-shoulder mentality.

Turner said UC Irvine, which earned the first NCAA Tournament victory in school history on Friday, has had to "live like little brothers" in the state to UCLA, USC, California, Stanford, San Diego State and "maybe some others."

"Well," Turner added, "little brother has been in the weight room, getting better, getting ready for a chance like this. ... You know, we need to stick our chests out a little bit right now."

Few teams are strutting like Oregon, led by savvy junior point guard Payton Pritchard, a starter on the team that reached the Final Four in 2017. He was the Most Outstanding Player of the Pac-12 tournament and followed with a team-high 19 against Wisconsin.

"He's been unbelievable," Altman said. "His aggressiveness, offensively and defensively; his leadership; toughness. He's been on another level here."

Freshman wing Louis King has averaged 17.8 points in the past four games. Wooten has blocked four shots in three consecutive games, providing elite rim protection.

"It's one thing to watch on tape and get a feel, but I thought they squeezed the floor," Wisconsin coach Greg Gard said of Oregon's defense. "Even when there weren't blocked shots, so to speak, they had bodies around. There was a presence around.

"And in order to counter that, you have to be able to make some perimeter shots to loosen them up and get them second guessing."

For UCI, that's where Hazzard and Leonard come in.

Leonard is shooting 41.2 percent from beyond the arc. Hazzard made 5 of 11 vs. Wisconsin, including a buzzer-beater to end the first half and something of a dagger with 1:26 to go. He is making 39.7 percent from 3-point range.

"Big-time players are supposed to make big-time plays, and I think I'm that, so I've got to keep doing that," Hazzard told TBS after Friday's game. "I've got a group of teammates that believe in me; I've got a coaching staff that believes in ... and obviously I believe in myself."

--Field Level Media