Hailing from Oakville, Ontario, Crepinsek began his Canadian amateur career with the Jr. B Oakville Buzz in 2006, with whom he won a Founders Cup.
He moved on to play for the Langley Thunder of the Western Lacrosse Association in 2013, and returned to the Rock, now based in Oakville, in 2014.
Crepinsek attended St. Thomas Aquinas Catholic Secondary School in Oakville, and went on to play lacrosse at the Rochester Institute of Technology, with whom he won three conference championships.
[1] Crepinsek was drafted with the last pick in the first round of the 2012 NLL Draft, and played all 16 games during his rookie season, collecting a Swarm rookie record of 18 loose balls in the process.
He was re-signed to a two-year contract extension after his rookie campaign.