2006-07: Jeffrey appeared in 68 regular season games for the Greyhounds and he recorded 34 goals and 58 assists. Jeffrey was also impressive in the OHL playoffs, scoring six goals and adding 12 assists in 13 contests.
2007-08: Led his team in scoring and was ninth in the entire OHL with 38 goals and 97 points despite only appearing in 56 games. Jeffrey also scored a goal in the Western Conference All-Stars game. The gritty forward finished third in scoring during the OHL playoff run and was invited to the WBS Penguins AHL playoff run where he scored 2 goals in 15 games.
2008-09: His first season of pro hockey came quick, splitting time between the big club and the minors. In 63 games with Wilkes-Barres, Jeffrey scored 11 goals and 37 points.
2009-10: Jeffrey continued his strong progression on a top Wilkes-Barres team, suiting up in 77 games with the Farm Club and scoring 71 points.
2010-11: Although he started the season in the AHL Jeffrey proved by mid-winter he had nothing left to do at the AHL level and was destined to play in the NHL in some capacity. With many of the Penguins prominent centers on the IR, Jeffrey was given as much icetime as he could handle, playing the point on the powerplay, centering a scoring line, and generally being used in every situation imaginable. In that 21 game stretch he managed 6 goals and 4 assists. Like many of the other Penguins centers though, Jeffrey saw his season end prematurely with a knee injury sustained on March 24th.
Jeffrey is a forward who has been offensively prolific wherever he has gone. Not the most naturally gifted forward, he has produces most of his offense through hard work and gritty play. He has a hard and accurate shot that he is able to use effectively from most areas of the offensive zone. He also has good instincts distributing the puck.
His greatest asset however is high compete level and solid work ethic. He plays an effective game defensively and is able to excel in whatever role and assignments given.