Zone defense is the flavor of the month. What was once thought to be a "less macho" approach is being used by Top 20 teams.

Teams who have historically utilized man-to-man schemes have showcased zone defense this spring. North Carolina shut down Maryland for three quarters with a zone defense and won. Expect Johns Hopkins to copy the Tar Heels' strategy and give the Terps a dosage of zone. Georgetown nearly upset Syracuse with a zone. Princeton, Hopkins, Syracuse and even Virginia are playing zone defense in 2011.

Why is a zone defense effective? Switching to a zone transforms an MMA brawl into a chess match.

"Make them think," Denver's Bill Tierney said. "We encourage our players to react and play, and when they are facing a zone, it adds a mental element that can slow the player down."

Stick technology has played a role in the new trend. Deeper pockets and tighter pinched sticks have made aggressive takeaway defense futile.

"The days are gone when the great programs will put six stud athletes on the field and ask them to defend one-on-one on an island. Every team has offensive players capable of making plays and beating their man," Tierney said.

Zones have long been used as a complementary defense, but this spring we're seeing more examples of zone used as the primary defense.

"Defensive coordinators can no longer just give an opponent a steady diet of one type of defense," Johns Hopkins coach Dave Pietramala said. "Zones are used as a change-up, to confuse the offense, to change the rhythm and the tempo of a game."

Switching to a zone often forces an unsuspecting opponent to burn a timeout to get organized.

"Zones are an attempt to slow down explosive offenses using the element of surprise," UNC coach Joe Breschi said. "Most programs are sprinkling in zone out of a timeout or at the end of a quarter, like basketball."

As offenses have become more complicated and multiple, defensive coordinators have been playing their trump card to simplify opponents schemes. If they are uncomfortable guarding a certain set in man-to-man defense, they play their trump card. Zone cancels offensive complexity.

A successful zone forces the offense to take shots that the defense wants them to take. A good goalie becomes great if he is well insulated by a tight zone. Coaches poach tactics from basketball.

"Today's zones are more aggressive, almost a man to man look, with ball pressure, which causes less opportunity for teams to diagnose and spin the ball with their hands free," Breschi said. "A great zone isn't passive."

Two external factors also contribute to the added frequency of zone defenses. Soft synthetic fields make a goalie's life easier, there aren't wicked bounce shots off hard dirt fields. Offenses no longer employ mammoth crease attackmen whose job it was to screen the goalie. Screeners have disappeared because of safety concerns.

What impact has the zone had? There are fewer possessions per team. The possessions are longer and games are lower scoring, because the clock ticks as a team probes the zone without a shot clock.

"There will be less goals scored in half field situations," Tierney said. "I think you'll see teams taking more chances in transition when they are facing a zone."

Some view zone defense as slow death. "Zone defense has it's flaws," Tierney said. "The flaws exist inside on the crease or with a lack of pressure behind. How do the zones rotate when they are forced to shift?"

Defenders are taught to knock down passes using active feet and hands. If done correctly, six defenders will move as one. But eventually skilled offensive players we decipher the code and generate quality shots. "The zone defenses have worked to a point, or until the offense figures out a way to beat it," Hofstra coach Seth Tierney said. "But the clock is ticking."

How do you beat the zone? Attack the gaps. "Make two defensive players play the ball," Seth Tierney said. "Draw two defenders and move the ball quickly around the perimeter, eventually forcing the defense to rotate."

"You must attack the zone. Most teams sit back when they see it and that slows the tempo of the game greatly," Breschi said. Don't get bunched up. Move into the gaps that a zone creates. Overload an area. Avoid unnecessary ball carrying which gives the defense a chance to reset.

"Make the extra pass and find the seams in the zone," says VMI coach Brian Anken. "Its not an athlete based offense, it's a knowledge and skill based offense."

Like basketball, team loos to dribble, penetrate a seam and dish the rock. It's important that your best shooters get their shots. When Maryland lost to North Carolina, left-handed wing shooter Travis Reed was injured and out of the lineup. When Virginia used a zone to beat the Tar Heels, UNC's main sniper, Marcus Holman, was on the sideline after the first quarter with an ankle injury.

Boston Cannons star Paul Rabil offers this advice: "The biggest challenge for the player is to be patient. I love it when teams go zone. It's not a matter of getting a shot. It becomes a matter of getting the best shot. It's important that midfielders understand the defensive rotation, don't be afraid to dodge the zone, and attack the rotation with ball movement."

Zone busters are a triple threats on the perimeter, able to shoot, penetrate or pass. Accurate stick work and a quick release are essential. And practice makes perfect. "We have never spent so much time in practice on a weekly basis, installing and drilling our zone offense," Seth Tierney said.

In 2003 Virginia used a zone defense coupled with a hot goalie and a muddy field to beat Hopkins in the NCAA title game. In 2004 Syracuse borrowed a page from Jim Boeheims book and used zone to fuel their title run. But the strategy has negatives.

Zone defense sacrifices time of possession. Late in a game when you are down three or four goals you can't play zone. You can't play zone of your goalie isn't good. Zone defense can hurt your transition, breaking out over the top of the offense is impossible. Many coaches fear that playing zone exclusively will hurt their man-to-man schemes and covering skills. Zones subtly can create lazy defenders.

Zone defense will be a storyline this weekend as Hopkins and Maryland face off on ESPNU at 8 p.m. Saturday. For the fans, watching an offense attack a zone defense without a shot clock requires patience. It may be the ideal time to run to the refrigerator for a refreshment. What looks like endless perimeter passing may actually be a play ultimately resulting in a high-percentage shot.

Tactics in lacrosse ebb and flow in a cyclical nature. Like it or not, zone defense are a staple of what we are seeing in 2011.

Quint Kessenich covers college sports for the ESPN networks and writes a column for The Baltimore Sun each Friday during lacrosse season.