Final Four 2015: Biggest X-Factors for Semifinal Matchups

Just because the calendar has turned to April doesn't mean that the madness is over. In fact, with four outstanding teams left standing in the Final Four, it might have just begun.

Along with an all-star roster of coaches, the co-favorites for the national Player of the Year award and three No. 1 seeds, we are getting two rematches this weekend. Kentucky and Wisconsin faced off last year in the same round of the tournament, with Kentucky surviving 74-73, while Duke and Michigan State, meanwhile, met in the Champions Classic back in November, with Duke winning 81-71.

We'll find out on Saturday whether those results will remain the same or if we're in for another NCAA tournament surprise.

Here are the X-factors to watch out for during the Final Four.

Kentucky's Shot-Blocking

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At this point in the season, the Wildcats just need to stick with what got them to 38-0. For Kentucky, that means staying aggressive defensively and continuing to block shots at an elite level.

This team is just filled with forceful players inside, particularly Willie Cauley-Stein and Karl-Anthony Towns. In just three seasons, Cauley-Stein is already second on Kentucky's all-time list of shot-blockers with 229. In just one season, Towns is 21st on that same list with 86.

In the semifinals, Kentucky will face an extremely physical Wisconsin team that has the size to match the Wildcats in a way that no team has all season long. For Kentucky to keep its advantage, shot-blocking will be key in establishing its athleticism and disrupting Wisconsin's offensive proficiency—the Badgers average 1.191 shots per possession, the best in the nation this year according to Team Rankings.

Wisconsin's Turnover Percentage

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On the other side of the ball, Wisconsin is going to need to continue to do what it does best: hold on to the ball, get offensive rebounds and make every offensive possession count against the vaunted Kentucky defense.

Obviously, this means that national Player of the Year candidate Frank Kaminsky is going to have to be aggressive on the boards, but it also means that the Badgers are going to need to hold on to the ball like they have all season—they had the lowest turnover percentage in the nation this year, according to Team Rankings..

Of course, Kentucky will make that extremely difficult in the semifinals with its size and forceful play, but when the ball is in Wisconsin's hands, it needs to stay there. The Badgers have been better on offense all season than most are giving them credit for, but if Kentucky is getting a lot of fast-break points, the Wildcats are going to be unstoppable.

Justise Winslow's Accuracy

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Jahlil Okafor has gotten most of the national attention directed at Duke this season, and rightly so—the freshman is a force to be reckoned with and is projected to be the top pick in the NBA draft this spring.

However, the key for Duke's Final Four success is Justise Winslow. The freshman has been on fire in the NCAA tournament, showing off his great transition skills and aggressive defense, but he's also added another element: scoring.

As Thayer Evans of Sports Illustrated points out, Winslow's improved shooting was a tremendous boost for Duke in March, particularly last weekend:  

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A talented scorer who can drive, hit jumpers and flourishes in transition, Winslow averaged 18.5 points and seven rebounds in his two games back home. The most frightening aspect of his game for Michigan State, Duke’s opponent in the Final Four on Saturday, is his improving three-point accuracy. He was five-for-eight from beyond the arc. Winslow has been creating matchup problems for opponents all season with his combination of size and speed, and Duke will need two of his best games to win a fifth national championship under Coach K.

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Winslow only averaged 12.5 points per game in the regular season, but in the Sweet 16 and Elite Eight he scored a combined 37 points. When Winslow keeps up that offensive production, he adds a much-needed element that stretches the focus of defenses beyond Okafor.

Travis Trice

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Michigan State's tournament run has been all about the coming together of its Big Three: Travis Trice, Denzel Valentine and Branden Dawson. However, nobody has been more of an X-factor than Trice, the senior guard from Ohio.

Trice has averaged nearly 20 points per game this NCAA tournament and has served as an emotional leader to his team. 

Bill Pennington of The New York Times describes just how surprising Trice's emergence has been:

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Michigan State is heading to the Final Four on the back of Trice, a small, skinny guard who was barely recruited out of high school, who was not a starter until this season and whose career was nearly derailed by a mysterious brain infection. He also had a litany of injuries in recent seasons, including a debilitating concussion.

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Now that Trice is healthy, he is a force of nature on the court and a calming presence in the huddle, where he encourages teammates who are struggling, eases the nerves of the inexperienced players and spreads the belief that the Spartans are going to win. 

Duke can't do anything about the intangibles that Trice brings to the team, but the Blue Devils will certainly try to stop Trice from scoring 24 points like he did in the Sweet 16 against Oklahoma. But if Trice can evade Duke's improved defense, he could spur his team on to yet another upset.

How Kentucky Deals with Pressure

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Every team left in the Final Four wants to win the championship, and every team has special players who won't be returning to college basketball next year and therefore are playing with a special sense of purpose. But no team is playing under the pressure of history like Kentucky is.

As John Calipari and his squad get closer to 40-0, the pressure is only going to increase. At this point, it's going to increase minute by minute. Notre Dame gave the Wildcats a real scare in the Elite Eight, but Kentucky thrived with its back against the wall, going 9-for-9 down the stretch and getting the win with clutch free-throw shooting, suffocating defense and Andrew Harrison's three-point magic.

That was big, because it showed that this Kentucky team can win close games against elite teams, something it hadn't been forced to do all season (with all respect to the Aggies, I don't consider Texas A&M elite).

But in the Final Four, the physicality of the game and the expectations on the table will be even greater. Kentucky has all of the talent and teamwork necessary to beat the remaining teams, but these remaining teams, particularly Wisconsin and Duke, are good enough to take advantage if Kentucky has a night riddled with nerves.

With history on the line, what's going on between Kentucky's ears will matter more than what's going on between the baskets.

Sam Dekker's Three-Point Shooting

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Sam Dekker is having an NCAA tournament for the ages, and he's going to need to keep excelling if Wisconsin wants to make it a step further than it did last season and get revenge on Kentucky.

In four NCAA tournament games so far, Dekker has averaged 21.75 points per game. He's been particularly lethal from beyond the arc, particularly in an astounding 5-for-6 performance against Arizona in the Elite Eight.

"[Among the] six featured scorers at the Final Four, Dekker ranks No. 1 in two-point tournament accuracy: 73 percent," ESPN Insider John Gasaway wrote. "Bo Ryan's junior is also tied with (Travis) Trice for made tournament threes with 13, and Dekker has achieved that figure on 48 percent shooting from beyond the arc."

Frank Kaminsky will likely attract a double-team wherever he goes, opening things up for Dekker to do damage outside. If he continues to be Mr. Automatic from three-point land, Wisconsin will be tough for even Kentucky to defend.

Duke's Perimeter Defense

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Michigan State is no doubt the most surprising team in the Final Four, and one of the big reasons why the Spartans have survived the month of March is their three-point shooting. The team has made nine three-point shots in each of its last two games against the strong defenses of Louisville and Oklahoma. 

Now it's up to Duke's perimeter defense to keep that in check in the Final Four.

The good news for the Blue Devils is that their perimeter defense has improved dramatically, particularly in the NCAA tournament. Earlier in the season, this team's perimeter defense was a huge liability, but against Gonzaga in the Elite Eight, Duke only allowed the Bulldogs to shoot 2-of-10 from beyond the arc.

Of course, Michigan State is a much better outside shooting team than Gonzaga, but still, it's crucial for the Blue Devils need to remain stingy from the perimeter. If they can shut down or at least contain that portion of the Spartans offense, they should find themselves in the championship game.

MIchigan State's Free-Throw Shooting

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While Michigan State needs to focus on nailing threes like it has all tournament, it's going to be key for the Spartans to draw fouls on defense, particularly against Jahlil Okafor, whose biggest weakness is his free-throw shooting.

However, the Spartans won't be able to take advantage of the fouls if they can't make their own free throws, an area in which they've struggled all season long. In fact, the team averages just 63.2 percent from the line, which has cost Michigan State some close games this year.

However, when it counted the most in the Elite Eight against Louisville, Michigan State was able to make the free throws, with Travis Trice and Denzel Valentine going 6-of-6 in the final 1:19 of the game.

"(Free throws) were my best friend because we made a couple, and they happened to miss one," Izzo told Allie LaForce of CBS after the game in Syracuse, New York (via MLive.com). "But we've been on that side of the coin before."