Regina improved their record to 12-8 while Edmonton dropped to 9-12.
With the score tied at five in the top of the 11th inning, Red Sox veteran second baseman Gabriel Montero doubled home teammate Aden Campbell for the go ahead run.
Montero had an all-star night at the plate as he reached base four times, scored two runs and had one RBI.
Skyler Henson picked up the win for the Red Sox while Sam Brunner pitched the 11th inning for the save.
The Red Sox board the bus and head to Fort McMurray to meet the Giants on Wednesday night for the historical first WMBL game at Shell Place.
(Courtesy Tony Playter/Outlaw Communications)