Belencoso fired Kitchee to the Hong Kong First Division title last term and has been in outstanding AFC Cup form, scoring 11 times in 10 appearances.
The 33-year-old forward - formerly of Albacete and Cadiz - has played a key role in Kitchee's progression and he was again on the scoresheet in the first leg, played earlier this month.
Luay Salah fired Iraq's Erbil into the lead in the 59th minute but it was that man Belencoso who responded in the 1-1 draw.
And Kitchee will have home ground advantage in the return clash as they look to reach the competition's final for the first time.
Erbil have previous pedigree in Asia's second-tier competition, having reached the final in 2012.
But that ended in a disappointing 4-0 loss to Al Kuwait, meaning Erbil will be determined to go one better.
And while Jose Francisco Molina's side have the luxury of being able to rely on Belencoso, Erbil also have a prolific Spanish striker of their own - Borja Rubiato having netted five times in the competition to date.
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