Nkwazi denied Zanaco a great opportunity to go three points clear after defeating the defending champions on Wednesday.
The Policemen knocked out Zanaco 1-0 in their delayed Week 17 match at Edwin Embolea Stadium in Lusaka.
Lameck Banda scored a 4th minute goal to dispatch Zanaco to their third league loss of the 2017 season.
Zanaco, though, stay top on goal difference with 50 points, tied with 2nd placed Green Buffaloes.
Nkwazi creep into 10th place from 12th on 38 points after collecting their ninth league win of the campaign.
Meanwhile, Zanaco’s defeat completed their games in hand joining the rest of FAZ Super League crew on 27 games.
With that factor, Zanaco now open another chapter on Sunday who will be engaged in a Week 28 winner-takes-all Lusaka derby showdown away at Buffaloes.
Winner on September 17 goes top as the plot thickens with eleven games left to play.