The win is Legon Cities heaviest since changing their name from Wa All Stars early this season.
Abubakari Abdul Latif started the scoring in the 11th minute through a free-kick.
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Nii Addy Ebenezer doubled the lead for Legon Cities in the 90th minute, before he executed the coup de grace in the added time to register a brace.
Legon Cities have matched on to the round of 32 stage of the MTN FA Cup.
The Royals as they are affectionately called are, however, inconsistent in the Ghana Premier League, lying 14th in the 18-club league with 14 points.
Legon Cities will stay at home and entertain Eleven Wonders on matchday 12 of the Ghana Premier League over the weakened when the GPL resumes.
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