Medlock's fourth field goal of the game, a 12-yarder late in the fourth quarter, gave him 60 on the season - one more than the 59 Dave Ridgway had with the Saskatchewan Roughriders in 1990.
The Redblacks (8-9-1) also made some history, becoming the first team in CFL history to win a division while posting a losing record.
The Blue Bombers finished the regular season 11-7.
Ottawa didn't play many of its starters Friday, including quarterbacks Henry Burris and Trevor Harris, the only two men to start at pivot for the team this season prior to Friday. Harris did throw one pass on a fake field-goal attempt in the fourth quarter, but the pass was incomplete.
Brock Jensen got the start in their place and split the duties with Danny O'Brien, who worked the middle two quarters.
With Winnipeg improving to 11-7, the B.C. Lions need to beat Saskatchewan on Saturday to finish at 12-6, and secure second-place in the CFL West. That would give them homefield in the Western Semifinal.
(The Canadian Press)