Gabler joined the Toronto Argonauts in 1966 out of Michigan and took over the starting QB spot in his rookie eason.  With only a 45.2% completion percentage, it was not the greatest start in CFL history, but Gablers numbers improved significantly in each of the next t wo years.  In 1967, he completed 50.2% of his passes and upped that again to 56.2% in 1968.  1968 was Gabler's best year in the leage as he threw for 3242 yards.  Gabler was traded to Winnipeg in a high profile deal, early in 1969.  The Argos got RB and future Hall of Famer Dave Raimey from Winnipeg in exchange for Gabler as Tom Wilkinson took over as the #1 pivot in Toronto.  Gabler's stay in Winnipeg last until about the halfway point of the following season (1970) when he was traded back East to Hamilton.  1970 was a so so season for Gabler, completing 52.1% of his passes, but throwing twice as many interceptions (20) as touchdowns (10).  In 1971, injuries limited Gabler to only 6 games and he lost the starting job to Joe Zuger in 1972 and was traded to Toronto for his second stint with the ARgos in what was his final season in the CFL.

For the seasons in which Gabler split time between teams, the official CFL stats did not give a breakdown by team.