5 storylines to watch in the Sweet 16

The opening weekend of the NCAA Tournament wasn't short on drama.

Multiple contenders were pushed to the limit, the defending champ was sent home early, and a 15-seed advanced to the regional semifinals for the second straight year.

Here are five storylines to keep an eye on when the Sweet 16 tips off Thursday.

Key injuries

Numerous schools are dealing with injuries to key players.

UCLA lost starting guard Jaime Jaquez to an ankle injury late in the second half of Saturday's matchup against Saint Mary's. Bruins head coach Mick Cronin wasn't overly optimistic postgame when asked about the junior's chances of playing against North Carolina. Jaquez is the team's second-leading scorer and one of the Pac-12's top defenders.

Michigan has been without starting point guard DeVante' Jones for most of its NCAA Tournament run. The Coastal Carolina transfer entered concussion protocol after 11 minutes of second-round action against Tennessee. Jones is averaging 10.4 points, 4.6 assists, 4.5 boards, and one steal over 32 appearances this season.

Unlike the aforementioned pair, Kerr Kriisa wasn't forced into an early exit from his team's most recent contest. However, the Arizona guard struggled mightily in his first game in 10 days, scoring just three points on 1-of-10 shooting. Kriisa's movement appeared compromised at times, and it's quite possible he hasn't fully recovered from a badly sprained ankle.

Houston has been without Marcus Sasser and Tramon Mark - two key players from last season's Final Four team - since December. While both were ruled out for the rest of the campaign, Sasser recently expressed some hope for a return depending on how far the Cougars go. The junior guard was averaging 17.7 points and 2.2 steals at the time of his injury.

Double-digit magic

At least one double-digit seed is guaranteed to reach the Elite Eight. Only six have made it one step further since the NCAA Tournament expanded to 64 schools in 1985.

Michigan might be the most talented squad from the four remaining double-digit seeds. The Wolverines are finally living up to their lofty preseason expectations, especially after taking out an in-form Tennessee fresh off an SEC Tournament title. Center Hunter Dickinson has been a two-way force and senior Eli Brooks has been an effective playmaker and defender. A strong start against Villanova in the regional semifinals is paramount; the Wildcats are 22-2 this season when leading at halftime and usually put teams away late with their top-ranked free-throw shooting.

Miami is through to its third Sweet 16 under Jim Larranaga thanks to outstanding defensive efforts; the Hurricanes forced 31 turnovers and racked up 22 steals over two NCAA Tournament games. Their ability to create havoc has fueled their transition offense, which included 30 fast-break points in the Round of 32 against No. 2 Auburn.

Iowa State is the only school to tally more steals than Miami during the Big Dance. The Cyclones have made opponents pay for their miscues, scoring 22 and 11 points off turnovers against LSU and Wisconsin, respectively. Additionally, the Tigers and Badgers combined to hit just six triples.

Saint Peter's is unquestionably the biggest surprise of the tourney. This year's MAAC Tournament champ followed up its upset of Kentucky with another stunning victory over the 31-win Murray State. The Peacocks' toughness and ability to get to the charity stripe have made up for their deficiencies in other areas.

Potential Duke, Gonzaga rematch

Both Gonzaga and Duke needed to dig deep to avoid an early exit from the Big Dance.

The tournament's No. 1 overall seed leaned on upperclassmen Drew Timme and Andrew Nembhard to fend off Memphis in the second round. Meanwhile, the Blue Devils' youth showed great poise as they overcame a five-point deficit late against Michigan State to reach the Sweet 16. Duke edged Gonzaga by three points in their thrilling encounter in Las Vegas last November. The stars from each side shone in the back-and-forth affair, but a rematch in the West regional final is far from guaranteed.

Arkansas plays hard defensively, returns multiple rotational players from last season's Elite Eight team, and could give the Bulldogs some trouble with its athleticism. Duke's offense faces a tougher challenge in the Sweet 16. Texas Tech sits No. 1 on KenPom's rankings for adjusted defensive efficiency and is allowing just 57.5 points on 35.5% shooting through the first two rounds.

Martin's resurgence

Big things were expected from Remy Martin when he arrived at Kansas last fall. The Arizona State transfer was coming off a strong four-year run with the Sun Devils where he earned Pac-12 Sixth Man of the Year honors and a pair of All-Pac-12 first-team selections.

Martin, the preseason Big 12 Player of the Year, was the Jayhawks' starting point guard on opening night. However, he was out of the first five by early January and sat out nearly a month due to a lingering knee injury. The fifth-year senior still wasn't himself when he returned but started to find his groove in the Big 12 Tournament.

That momentum has carried over to the NCAA tourney. Martin has provided a much-needed spark off the bench, averaging 17.5 points on 59.1% shooting to go along with four boards, four assists, and one steal during Kansas' run.

The Jayhawks reach another level when they get this type of production from Martin. His outside shooting and ability to drive-and-kick will be important against Providence, which has defended the 3-pointer well this season.

Painter seeks elusive Final Four

Matt Painter may never get a better shot to reach his first career Final Four. He's got an electric offense led by budding star Jaden Ivey and arguably the nation's best big man tandem in 7-foot-4 center Zach Edey and Big Ten Sixth Man of the Year Trevion Williams.

The draw is also in Purdue's favor with Baylor and Kentucky out of the picture. The Boilermakers should overwhelm Saint Peter's with their size, as nobody in the Peacocks' rotation stands taller than 6-foot-7. UCLA or North Carolina awaits next in the regional final. Two of the Bruins' losses this season came against Arizona, which boasts its own towering duo but is on the other side of the bracket.

Although defense isn't Purdue's strong suit, Edey and Williams should be able to match up against Tar Heels star Armando Bacot. The junior was limited to two points before fouling out in the Boilermakers' 93-84 victory last November.

Purdue's biggest concern might be defending Brady Manek and North Carolina's outside threats. Marquette transfer Dawson Garcia (who won't be available due to personal reasons) found great success as a stretch-four in their previous meeting, which bodes well for Manek. Hubert Davis' squad ranks 49th in 3-point efficiency, while Painter's unit is 297th in triples allowed per contest.