From 1972 until 1977, the OPJHL shared their region with the Southern Ontario Junior A Hockey League.
What filled the gap in 1972 was the 12-team Ontario Hockey Association Jr. "A" Hockey League, which comprised five teams leaving the Metro Junior "B" (the Richmond Hill Rams, North York Rangers, Downsview Beavers, Aurora Tigers and the Dixie Beehives), 6 expansion teams (Seneca Flyers, Ajax Steelers, Wexford Warriors, Vaughan Nationals, Weston Dodgers), the Kingston Frontenacs of the defunct Eastern Junior B Hockey League, and the North Bay Trappers of the recently folded Northern Ontario Junior Hockey League [1].
The final chapter of this saga was slightly redemptive for the OPJHL as their North York Rangers went the distance and defeated Guelph 4-games-to-3.
The Guelph Platers and Hamilton Mountain A's jumped to the OPJHL, while the Owen Sound Greys took a season off then joined the Georgian Bay Intermediate A Hockey League and the Collingwood Blues changed their name and dropped to Junior C. After a five-year feud, the SOJAHL won the battle but lost the war as their champions won three of five OHA Championships but ultimately folded.
The four remaining teams at the end of the OHA Jr. "A" League era were the Final Champion Owen Sound Greys, the Aurora Eagles, the Markham Waxers, and the Richmond Hill Dynes [9].