Zesco United saw their lead cut from three to one point on Sunday.
The FAZ Super Division leaders were held to a 0-0 away draw by relegation battling Green Eagles in Choma.
Zesco must now beat fourth from bottom Mufulira Wanderers this Saturday to clinch the title.
Zesco have 71 points, one ahead of Zanaco and Green Buffaloes w ho are tied on71 points.
Zanaco beat Buildcon 2-1 away in Ndola on the same day.
Zanaco captain Ziyo Tembo put the visitors ahead in the 18th minute before Buildcon defender Christopher Munthali turned the ball into his own net in the 18th minute.
Geoffrey Sserukuma cut that lead with Buildcon’s lone goal in the 28th minute.
And at Nkoloma Stadium in Lusaka, Buffaloes also beat Red Arrows 2-1.
Ex- Zambia midfielder Felix Katongo put Buffaloes ahead in the 36th minute before striker Friday Samu added the second on the stroke of halftime.
Striker Lubinda Mundia scored Arrows consolation goal in the 67th minute.
Meanwhile, in their final league fixtures, Zesco hosts Wanderers, Zanaco are home against Forest Rangers while Buffaloes await Green Eagles.