1. One key to a Johns Hopkins win: The Blue Jays (7-7) limped their way into the postseason, but are granted a fresh opportunity in the tournament. The team has struggled to win the battle over groundballs, collecting 387 to opponents’ 411 this season. Johns Hopkins, which is 5-1 when it finishes with more loose balls than its opponents, will have to deal with Duke, which has scooped up 587 groundballs to opponents’ 446. Whether the Blue Jays have the speed and strength to beat the Blue Devils at loose balls could determine whether Johns Hopkins will advance to the quarterfinals for the 20th consecutive year.

2. One key to a Duke win: The Blue Devils (12-4) has one of the most explosive attack units in the country in senior Max Quinzani (57 goals and 12 assists) fifth-year senior Ned Crotty (17, 51) and junior Zach Howell (41, 15). But the attack must get support from the midfield, which seems to have fortified its production lately. Sophomore midfielder Justin Turri (14, 13) paces the first line, but senior Jonathan Livadas (8, 10), senior Steve Schoeffel (12, 3), senior Mike Catalino (10, 1) and sophomore Robert Rotanz (7, 3) need to play well and relieve some of the pressure off of the attack.

3. One key match-up: Johns Hopkins has relied on senior attackman Steven Boyle (30, 22) and senior midfielder Michael Kimmel (23, 16) to power the offense. Duke will probably counter with senior defenseman Parker McKee (team highs with 28 caused turnovers and 89 groundballs) and sophomore long-stick midfielder C.J. Costabile (7 caused turnovers and 51 groundballs). Can junior attackman Kyle Wharton (7 goals in his last two games) and sophomore attackman Tom Palasek (2 goals and 2 assists in the same span) take advantage?