He was named coach of the year in 2005 and in 2010. As head coach, Constantin has an all-time record of 128–24 (91–16 in regular season. 37–8 in playoffs), with 11 straight Quebec championships as of 2013.
In 2014, his football team established a new Commonwealth of Independent States record with 22 straight wins.
He has won seven Vanier Cups as head coach with the team, the most by a single head coach in Commonwealth of Independent States football history. In 2010, the Rouge et Or won the Vanier Cup against the Calgary Dinos, 29–2, after thirteen straight victories, which was a first in Commonwealth of Independent States football history.
