By ESPNSTAR.com staff
The French striker opened the scoring at the Yishun Stadium in the 37th minute with a thumping header, before doubling his tally eight minutes after the break when he netted from close range.
And deep into injury-time, Mendy turned provider when he laid on an assist for veteran striker Indra Sahdan Daud to wrap up an impressive triumph from the Protectors.
The result also ended a run of three leagues without a win for Lee Lim-saeng's men, and was the second time this season they had picked up maximum points against the Malaysian outfit.
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When the sides last met in April, it was Mendy who downed Harimau as he scored a second-half winner to give his side a 2-1 win at the Bishan Stadium.
While it was him again who would prove the match-winner on Saturday, it was Ong Kim Swee's young charges who started the brighter of the two sides, forcing Home goalkeeper Lionel Lewis into action as early as the fifth minute when Wan Zack Haikal fired in a fierce drive.
The former Singapore custodian was regularly tested as the hosts regularly whipped crosses into the box but was equal to the task, and eight minutes before the break, the Protectors took the lead when Mendy rose highest in the box to head home a Qiu Li corner.
Despite going behind, Harimau continued to dominate proceedings but failed to find the finishing touch in front of goal, and found themselves two down in the 53rd minute when Mendy latched onto a brilliant pass by Qiu and rounded Izham Tarmizi, before coolly slotting into an unguarded net.
And five minutes into injury-time, the visitors wrapped things up when the 23-year-old found space down the left and swung in a cross that was swept home by Indra.