After both sides lost to Gor Mahia in their last league outings, they were desperate to get something from the game.
The visitors needed points to get out of the relegation zone, with the hosts needing maximum points to surge upwards on the log.
Last season's MVP Erick Kapaito gave the Shield Cup champions the lead after just 20 minutes following a perfect move that left their visitors open at the back.
The goal was a wake-up call for the struggling Zoo, who fought hard for an equaliser, and they were rewarded after a half an hour when Kevin Omondi powered home from close range.
Following the outcome, Sharks are placed seventh on the log with 30 points after 20 games, with Zoo rooted in the 16th position on 17 points.