Navy opened up a 3-0 lead after senior attack Ben Horn (Mill Valley, Calif.) produced two of his three goals in the first 20 minutes of the contest.
The second quarter leant itself to goals aplenty, as Bucknell worked its way back into the contest by scoring four goals - all by a different player. Navy, though, held tough and owned a narrow 5-4 lead at the half.
The Mids scored the first two goals of the third quarter and held the red-hot Bison scoreless until Christensen fired in his second goal with 11 ticks left on the clock.
Honorable Mention All-American Chris Cara got the Bison to within one, 7-6, when he scored his second goal just 53 seconds into the fourth quarter.
The Bison knotted the game at 7-7 after Navy goalkeeper Matt Russell (Madison, Conn.) threw an outlet pass to defensive midfielder Dan Harris (Manlius, N.Y.) 10 yards in front of the Mids' goal. Harris was leveled and BU attack Kirk Klett quickly took the ball and tucked it in past Russell.
Navy, who had been called for just six penalties in three games going into the game, was whistled for eight on the afternoon, including five in the first half. The Mids' foul trouble would be what sealed their fate as Bucknell scored its second extra-man goal in eight tries on the most important possession of the game.
Bucknell scored the final four goals of the contest leaving Navy without a goal since the 3:01 mark in the third quarter.
The Bison outshot Navy, 43-30, while Bucknell goalkeeper Matt Baran collected one more save (12) than Navy's Russell (11).
Though Navy held the face-off advantage, 11-8, the Mids obviously struggled without Preseason All-American Chris Pieczonka (Hamburg, N.Y.) who was injured on a face-off after Bucknell's first goal at 11:04 in the second quarter. Sophomores Tommy Wallin (Mountain Lakes, N.J.) and William Wallace (Bloomfield Village, Mich.) replaced Pieczonka in the lineup with Wallin winning six of the 11 draws he took and Wallace claimed one of his two face-offs.
Horn led Navy with three goals, while freshman attack Nick Mirabito (Binghamton, N.Y.) added a pair. Gill turned in a team-high three assists for the Mids. The Bison did a fine job on Navy leading scorers Steve Looney (Silver Spring, Md.) and Jon Birsner (Levittown, N.Y.). Looney scored a goal and added an assist, while an ailing Birsner was held without any points.
Bucknell was led by Christensen's trio of goals, while he also added an assist and Case added a goal to his three assists.
The Midshipmen return to action Tuesday when they play host to Lafayette. Game time is set for 12-Noon at Navy-Marine Corps Memorial Stadium.