•Prisons centre player Jairus Kipkosgei was stretchered off after twisting his ankle at the end of the second set, limiting David Lung'aho's options in the position.
•Elsewhere, KPA came from two sets down to prevail over newbies Trailblazers 3-2.
General Service Unit (GSU) head coach Gideon Tarus has asked his players to amend their service and reception flaws despite their 3-1 win over Kenya Prisons in the national men's volleyball playoffs at Nyayo Stadium gymnasium on Friday.
Sets of 25-20, 19-25, 25-21 and 28-26, powered the paramilitary side to victory to kick off their title defence on the front foot.
GSU have won the last four editions of the competition but Tarus still feels his charges did not play up to their strength.
"We played well but forced errors saw us lose the second set. Reception and service still need to be worked on. We can't afford to donate sets in the remaining matches because it might affect us after the last match."
Prisons centre player Jairus Kipkosgei was stretchered off after twisting his ankle at the end of the second set, limiting David Lung'aho's options in the position.
He is set for a spell on the sidelines in a major blow to the Warders who tackle KPA tomorrow and Trailblazers on Sunday.
"Injury to Kipkosgei played a part in the defeat. Losing the first set destabilised the players because had we won, it would have changed so many things in the subsequent sets," Lung'aho observed.
He added: "I am happy with the performance because GSU is used to humiliating us in straight sets. We just need to scalp KPA and Trailblazers and see what happens."
GSU led 20-18 in the first technical time out before peeling away to bag the first set 25-20. Naftali Chumba proved once again why coach Gideon Tarus rates him highly.
Determined to redeem their dwindling fortunes, Prisons made life difficult for GSU in the second set and even led 15-11. They then widened the gap to 20-14 and eventually won 25-19 to make it 1-1. GSU re-discovered their mojo and made it 2-1 courtesy of 25-21.
Though the introduction of Michael Chemos in the fourth set brought belief to Prisons, they could not stop GSU from sealing the victory 28-26.
Elsewhere, KPA came from two sets down to prevail over newbies Trailblazers 3-2. KPA were far from their imperial best in the opening two sets with a lack of cohesion being their greatest undoing losing 25-22, 25-22.
The Sammy Mulinge-coached team bounced back from the setback to claim victory in sets of 25-23, 25-17 and 15-11.
KPA take on Kenya Prisons today as GSU entertain Trailblazers.