The court heard that one of the teenagers met Guembes in Guildford on 19 January before walking with him to Stoke Park, where the other waited.
Prosecutors said Guembes, as part of a “ruse concocted to lure him to the park”, had been told he was going there to rob another boy.
Both attackers had knives but their victim did not, jurors were told.
They heard Guembes had tried to fight back despite being outnumbered but was stabbed in the head, shoulder and lower back. He was left at the scene as his killers fled.
Emergency services were called by members of the public but the 15-year-old was pronounced dead in the park.
Following his death, Guembes’s family described him as a “kind young boy, caring friend and a talented footballer”.
“We regret that fatal day but we praise and adore all the time we spent together,” they said in a statement.
All Hallows Catholic School in Farnham, which the 15-year-old attended, said he was “an incredible young man” who had “embraced every opportunity and new experience with excitement and energy that inspired those around him”.
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