The 2008 league champions suffered a second defeat after falling 4-1 to Batoto ba Mungu in the Kenyan Premier League match played at Kasarani Stadium.
Kimanzi, who is now tied jointly top with Bandari, blamed his players for losing more grounds after surrendering a five-point lead.
"We made mistakes; team mistakes that led to us conceding the goals. We played like we did not want to win as compared to Sofapaka, who showed they desperately needed the win.
"In the last twenty minutes we tried to play well, but had already lost it. It was difficult to get back into the game because we were three goals down. It could have been better if we could have started early, not when things are bad."
The ‘Slum Boys’ still top the league with twenty-five points, same as second-placed Bandari, who has an inferior goal difference.