In 31 days, two teams will meet in Philadelphia for the men's lacrosse national championship.

Who that will be is anyone's guess. With unparalleled parity in the sport, the race is wide-open. This weekend, the best slate of the season, will go a long way toward winnowing the field.

Some teams, such as Johns Hopkins and Colgate, need a win to keep their NCAA tournament hopes alive. Others, like defending national champion Loyola and Syracuse, want to burnish their resume.

These seven games will go a long way toward deciding who will have a shot at Championship Weekend.

Maryland vs. Virginia

ACC semifinal

Friday, 5 p.m. in Chapel Hill, N.C. (ESPNU)

What's at stake?

The Cavaliers (6-7) must win the Atlantic Coast Conference title to have a shot at an at-large bid to the NCAA tournament. The Cavs showed a flicker of offensive life in a late-season loss to Duke. For the Terps, (9-2) a win would solidify their strong at-large resume and cement a home playoff game. This team has big dreams but hasn't been playing like a team destined for Memorial Day.

Who to watch?

In their regular-season meeting, Maryland ran on Virginia, with goalie Niko Amato hitting Jesse Bernhardt twice for transition goals. The Terps defenders, led by Michael Ehrhardt, Goran Murray and Landon Carr, funneled Virginia dodgers to weak-angle shots, protecting the paint well.

"Maryland understands the team concept, doesn't care so much with identifying who is playing attack, who's in the midfield. They will interchange their guys throughout the game, and it's proved to be successful," ESPN announcer Mike Corey said. "They've lost only two games all year, to two of the top teams in the nation [North Carolina and Johns Hopkins]."

Virginia has struggled up the middle of the field — goaltending, faceoffs and finishing shots. Mark Cockerton has been the mainstay, averaging 3.5 goals per game. The Wahoos are No. 1 in the nation in ground balls (40.77 per game) and fourth in fewest turnovers, with only 12.85 per contest. The Cavs need a midfielder like Rob Emery, Matt White or Ryan Tucker (Gilman) to step up, and they can't afford to shoot less than 25 percent.

What will make the difference?

Amato gives Maryland a sizable advantage in goal. The Terps failed to knock out Hopkins when presented with a similar opportunity two weeks ago. They need to demonstrate a killer instinct and send the Cavs packing to an early summer vacation.

Duke vs. North Carolina

ACC semifinal

Friday, 7:30 p.m. in Chapel Hill (ESPNU)

What's at stake?

The winner earns a trip to the ACC final on Sunday and likely a home game in the NCAA tournament. The Tar Heels (10-3) have won seven in row since falling to the Blue Devils, 11-8, on March 13. Duke (11-4) is also on fire, winners of nine straight games, In his career, coach John Danowski is 18-2 against North Carolina.