The green-shirts led the first half 3-2 as heavy thunderstorm stopped play for some time in the second half.
Arsalan hammered the goals in 21st, 50th and 63rd minutes.
Mohammad Zubair, Syed Kashif Shah and Mohammad Suleman scored one goal each in sixth, 14th and 60th minute respectively.
For Ghana, Mathew Damalie, Ifred Ntiamoah and Samuel Afari scored one goal apiece in 19th, 35th and 59th minute.
Pakistan team will play their second match of the Olympic event against Chile on Wednesday.—APP
