In 2011: With team but did not play ... In 2010: Played in 11 games as a rookie, primarily on man-up offense ... Scored three goals, all in EMO situations ... First career goal came on opening day against No. 1 Duke ... Also scored against Navy and Jacksonville ... Took season-high four shots against Holy Cross ... Personal: Son of Tom and Robin Mattimore ... Born Sept. 14, 1990 in Chicago ... Has four siblings, Thomas, Tess, Kate and Annie ... Thomas plays lacrosse at Dartmouth ... Father played football at Bowling Green ... Earned four letters in lacrosse and two in football at St. Ignatius Prep in San Francisco, the same school that produced former Bucknell all-conference defenseman Michael Abou Jaoude ... Earned high school All-America honors ... Team captain ... As a senior had 67 goals and 57 assists while helping team to 21-1 record ... Team was ranked No. 1 in the state and No. 30 in the nation ... Received the Brophy Award as the top male athlete in his school ... Majoring in history ... Frank Fedorjaka on Mattimore: "Billy has worked extremely hard over the last year, came back in great shape, and now is knocking on the door for a first-line midfield spot. He was the leader of our scout team last season, and I think he grew a lot from that experience. He is a strong bull dodger and I'd say one of the most improved players on the team."