And Powell accused Pirates player-manager Stuart Campbell of getting Jose Semedo dismissed by overreacting to a 60th-minute aerial challenge.
Kyle Reid had already received a red card six minutes earlier for a late challenge on James Tunnicliffe - a second caution Powell had no argument with. The Rovers centre-back left the field on a stretcher.
Powell was bitterly upset as his side were cruising through an eighth-minute header from Paul Benson and a 46th-minute strike from Kyel Reid before having the two men sent off.
"Stuart is fighting for his team's life in this division but when you see a player-manager wink at the fans and clap his bench, having got an opponent sent off, something is wrong," said Powell.
"The referee gave us nothing all game. I was told by him to leave the dugout because I complained that Gavin Williams had handled the ball before shooting Rovers' equaliser.
"It was a bizarre afternoon and I feel as though we lost the game. The players showed tremendous character with nine men but until the red cards we were in control."
Source: PA
Source: PA