Vipers SC opened a seven-point gap on top of the Ugandan Premier League table after defeating struggling Proline 4-2 on Tuesday.
The relegation-threatened hosts opened the scoring in the eighth minute when Hamisi Kiiza capitalized on a goalkeeping error to put his team on the lead.
However, the league leaders levelled matters three minutes later when Denis Mwemezi found space in the danger zone and placed the ball in the bottom corner.
It got worse for Proline in the 13th minute when Fahad Bayo pounced on a rebound to give the Venoms a deserved lead.
Mwemezi made it 3-1 in the 19th minute as the hosts crumbled under pressure from the visitors.
Bayo completed his brace from the penalty spot in the 57th minute - Ibrahim Sendi committed a foul in the danger zone, and the referee awarded the visitors a penalty and the striker made no mistake with his spot-kick.
Hakim Kiwanuka scored for Proline in the 85th minute to make it 4-2 but the damage had already been done.
KCCA lost more ground as they fell away against Bright Stars 2-1 in another top tier clash.
Joseph Janjali scored for the hosts in the first minute but Muzamiru Mutyaba levelled the scores a minute to the break. Stars pushed harder for the win and it came in the 77th minute courtesy of Ronald Sempala.
In other results, Villa SC fell at home by a solitary goal against Busoga while Onduparaka were held to a 1-1 draw by Maroons.