The Maryland Interscholastic Athletic Association A Conference boys lacrosse semifinals are set for tonight at Towson University's Johnny Unitas Stadium, with No.1 Calvert Hall taking on defending champ and No. 3 St. Paul's at 6 p.m., followed by No. 2 Gilman vs. No. 4 Boys' Latin at 8:30. Here's a breakdown with a berth in Friday's championship game (8 p.m. at Unitas Stadium) on the line:

Calvert Hall (16-1) vs. St. Paul's (13-7)

This is a classic matchup between youth and experience. All season, the No. 1 Cardinals have successfully answered questions about their young roster -- finishing with the league's best record and avenging their only loss against McDonogh. After receiving a first-round bye for capturing the league's Black Division, they have the chore of defeating the defending league champs for a third time this season. The Cardinals have every inch of the field covered with talent, led by junior attackman Patrick Kelly, sophomore midfielder Stephen Kelly, and junior defenseman Evan Connell. The Crusaders, who reached the semifinals with a 9-8 win at St. Mary's, counter with valuable championship experience. Seniors Taylor Michel and Jay Carlson on offense and fellow senior goalie Gunnar Waldt in back have all thrived in big games. Calvert Hall got past St. Paul's twice this season -- 5-4 on March 29 and 9-6 on April 19.

Gilman (11-5) vs. Boys' Latin (11-7)

One goal separated the teams in two Gilman wins during the regular season -- 8-7 in overtime on April 8 and 12-11 on May 3. Another tight game is almost a guarantee with both teams bringing plenty of talent. Gilman earned a first-round bye after capturing the league's Red Division, while the Lakers added momentum with a gutsy 8-7 win at McDonogh in the quarterfinals. All-Metro attackman Wells Stanwick led the offense with one goal and four assists, but their defense is what got the job done in the end -- limiting the Eagles to one goal for the final 23 minutes, 54 seconds. After an inconsistent regular season featuring a handful of one-goal losses, the Lakers appear to have a new lease on life that started with a double-overtime win against St. Paul's in their regular-season finale. Gilman, led by seniors Conor Doyle and Ryan Tucker, will try to thwart the Laker's surge by controlling possession. The Greyhounds have received fine play in goal from Palmer Murray.