Highlanders rearguard was at fault as they fell to neighbours Chicken Inn in an entertaining Bulawayo derby at Barbourfields yesterday.
It was Bosso's first defeat of the season but they stayed at the top of the standings despite the loss.
They have 14 points from seven games.
Second placed Simba Bhora who are on 13 points were playing across town at Luveve where they lost 1-0 to Bulawayo Chiefs.
Bosso were forced to make adjustments to their backline owing to the absence of the suspended Marvelous Chigumira.
Their back up plan was poor and Chicken Inn punished them for that.
Chigumira, who plays as the right back was replaced by Andrew Mbeba, who was shifted from his usual central position.
Debutant Brian Mlotshwa was brought in to partner Peter Muduhwa in the heart of the defence while Archford Faira kept his place at left back.
It was a bad debut as he lasted 23 minutes on the field and was pulled out with Chicken Inn 2-0 up.
Mlotshwa, together with leftback Faira, failed to deal with a Brian Muza run on the break allowing the forward to fire home from just outside box after seven minutes.
Muza made a solo run from the centre of the park.
Ariel Sibanda was also to blame as Muza's grounder hit the post and the ball hit him to cross the line. Chicken Inn would double their lead after 16 minutes of play through Michael Charamba, who capitalised on a Bosso defensive blunder.
Mlotshwa fed Ariel Sibanda what appeared to be an awkward pass inside the box with Chicken Inn high on the press.
In trying to clear the danger, Sibanda sent the ball onto the path of Charamba who fired home to put Chicken Inn 2-0 up.
Realising things could become worse, Bosso restructured their backline in the 23rd minute taking out Mlotshwa while bringing in Mvelo Khoza to take up the right back position while Mbeba reverted to partnering Muduhwa in central defence.
It seemed to be a perfect move as Bosso suddenly turned up the heat and began to dominate the game.
They were rewarded with a goal 10 minutes before the break with Lynoth Chikuhwa slotting home from inside the box.
In the 53rd minute a well worked move involving Charamba and George Majika drew a good save from Sibanda.
There was a comical moment with 20 minutes left as Bernard went in chase of Chikuhwa who had grabbed a water bottle in Bernard's goal.
On the other end, Sibanda made a great low save to deny Innocent Muchaneka after 77 minutes.
The goal was his fifth for the season.
Bosso coach Kelvin Kaindu felt it was a painful defeat.
"It was a painful defeat. You could see even from the players on the bench that we have a team that is ready to compete for the championship. We lost a game where we made our own mistakes and we were punished by our opponents. Even before the game we knew this was going to be a difficult game," said Kaindu.
On Mlotshwa's debut, Kaindu said: " As a coach you don't want to take out a player like that but l think the pressure was going to be too much if we had kept him on."
Chicken Inn coach Joey Antipas thought their game plan worked perfectly.
"Playing Highlanders is not an easy task. The boys did well throughout the 90 minutes. Also we had a game plan for them. We intended to attack them from the beginning and we did that.
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"We knew their defenders, when on the ball and under pressure, t'panic and that is exactly what happened. So everything was according to the script. We wanted to press them and score early goals," said Antipas.
Teams
Highlanders FC
A Sibanda, B Mlotshwa (M Khosa 23'), A Faira, A Mbeba, P Muduhwa, M Ncube, P Ndlovu (R Sibanda 84'), D Mhindirira, L Chikuhwa (B Ndlovu 80'), M Mushore, B Ncube
Chicken Inn FC
D Bernard, J Tulani, X Ndlovu, I Mabunu, K Chinda, D Phiri, M Hwata (B Rendo 54'), M Charamba, B Muza, L Mangaira, G Majika (B Mpofu 70')
