2002-03: O’Neill spent the season with the USHL’s Green Bay Gamblers. He scored two goals and added 15 assists on the year. He was also selected to play in the USHL all-star game. O’Neill garnered a great deal of tournament experience representing Ontario on the Under 17 team in Halifax as well as the Canadian Under 18 Select Championship in the Czech Republic. Selected second overall by the Kingston Frontenacs in the 2002 OHL priority draft, O’Neill opted instead to play college hockey with Notre Dame.
2003-04: O’Neill earned a regular shift on the Irish blueline as a 17-year-old freshman. He scored two goals and 10 assists in 39 games and recorded a promising +7 rating on the year. O’Neill earned CCHA all—rookie team honorable mention. He was also one of only two college players to represent Canada at the IIHF U-18 World Championships in Minsk. He had a goal, an assist and a +4 rating in seven games.
2004-05: As a sophomore defenseman for Irish, O’Neill was the stalwart on a lackluster Notre Dame team. O’Neill’s 20 points in 38 games were second only to senior forward Cory Mclean’s 22-point effort. O’Neill was a -21 for the season, but such numbers are to be expected from a player who logs a ton of ice time on a struggling team.
2006-07: In his final season with the University of Notre Dame (CCHA), the defenseman tallied three goals and 21 points in 42 games, along with his first CCHA title.
2007-08: In his first year of professional hockey, O’Neill joined up with the Lake Erie Monsters (AHL). In 51 games, he tallied a pair of goals and six points, along with 50 minutes in the penalty box. He spent another six games with Johnstown (ECHL), registering one assists in his time with the Chiefs.
2008-09: O’Neill spent the majority of the season with Lake Erie (AHL), where he tallied a goal and six points in 54 games. He also saw action with the Johnstown Chiefs (ECHL), registering one helper in six contests. This season also marked the D-man’s first look at the NHL, when he spent three games with the Avalanche. He’ll be back with the Monsters for his third AHL season in 2009-10.
O’Neill is a big and strong defender who plays a solid two-way game. He is not afraid to hit, relying on his size to intimidate opponents who challenge him into a physical confrontation. O’Neill also frequently joins the rush, with his long stride enabling him to keep up with more fleet-footed forwards. His 73 shots (second on the team) are also a strong indication of O’Neill’s prowess in the attacking zone. O’Neill plays in all situations for the Irish, and often times is set up on the power play to deliver one-timers on net. He has improved with his decision making, although he is prone to attempting long distance passes that occasionally end up on the opposing team’s sticks.