From Justice League of America, Volume 1, Issue #141 (DC, April 1977) :
An energy discharge from a Manhunter takes Black Canary down. There is a shot of her out cold on the ground, recovering, but still looking groggy (needing to sit). When we next see her, she has been subdued again, and is unconscious. Wonder Woman attempts to rescue Canary and her comrades, but is blasted from behind, and collapses. Very nice scene!
Source: My Collection