Defender Joash Onyango was sent off in the 54th minute for a second bookable offence but Gor Mahia went on to dominate proceedings and even created decent chances that were not converted.
The AFC Leopards Junior team coach has however, lauded the tactician for his perfect strategy.
“After they (Gor Mahia) were reduced to ten men, I feel Kerr panicked a little and made unnecessary substitutions. But his tactics were on point, he is a good coach who knows how to push his team and get results, that one I cannot deny.
“One thing he has to try and work on is the finishing, the rate of conversion is low and that is not good,” Ambani told Goal.
Gor Mahia is second in Group D of the Caf Confederation Cup with two points while USM Alger are top on four.