Prior to Monday's win, the administrative side had never defeated Wekundu wa Msimbazi in 18 meetings
Simba SC have suffered their second league loss in as many matches after falling by a solitary goal to Ruvu Shooting in a match played at Uhuru Stadium.
The defending champions came into the match hoping to return to winning ways after a 1-0 loss in their last outing against Tanzania Prisons. In the reverse fixture last season, the administrative side played to a 1-1 draw, the second time they had achieved the same over the Msimbazi-based charges.
Prior to Monday's meeting, the two teams had met 18 times in all competitions and Wekundu wa msimbazi had managed to win 16 games, drawing the remaining two.
Fans had every reason to look into Monday's game, optimistic of getting maximum points.
Coach Sven Vandenbroeck tinkered with his squad, giving Beno Kakolanya and Francis Kahata a chance. Bernard Morrison, the returning John Bocco, and Aishi Manula were the players who started on the bench.
Early proceedings were not encouraging; as the visitors needed just 35 minutes to open the scoring.
Fully Zulu Maganga outpaced his markers before playing the ball to his colleague whose first touch set the skipper in a one on one situation with Kakolanya.
Maganga made no mistake from three yards, sending his team into the break with a deserving lead.
Simba were given a lifeline in the 80th minute when they were awarded a penalty after a foul play by their opponents in the danger zone. Bocco, who had been introduced, took it but despite beating the goalkeeper, he could not beat the crossbar.
Monday's loss casts doubt on the future of Vandenbroeck who has arguably the best squad in the Tanzania Mainland League.
Wekundu wa Msimbazi have now dropped to fourth position with 13 points from seven games.
Azam FC also fell for the first time this season by a solitary goal to their hosts Mtibwa Sugar. Jaffary Kibaya scored the lone goal in the 62nd minute to hand the Sugar Millers maximum points.
Tanzania Prisons also defeated their hosts Dodoma Jiji by the same margin, with Ramadhan Ibata scoring the only goal.
Azam are still leading the race with 21 points after eight games, followed by Yanga SC who have two points less after seven games. Biashara Mara United are third with 16 points after eight games.