The Hearts of Oak striker's goal in the play-off fixture at Stade Lat-Dior in Thies earned the Black Stars a place in the quarter-final of the Cup competition where they will face Burkina Faso on Thursday.
The Scorpions, on the other hand, have been demoted to the Plate Competition, a championship for the eight losing teams in the play-off round.
With players from Asante Kotoko only just joining Ghana's camp ahead of kick-off due to a Caf Champions League fixture in Tunisia on Sunday, Hearts of Oak and Ashanti Gold dominated coach Maxwell Konadu's starting line-up. Each club has four players.
Mohammed Alhassan, Joseph Esso, Benjamin Afutu and Mohammed Fatawu - all of Hearts - made the XI as did AshGold's Abdul Latif Anabila, James Akaminko, Appiah MacCarthy and captain Mumuni Shafiu.
The Black Stars started as the brighter side, the Gambians opting to sit back and play on the counter. Only a few scoring chances were created in the opening moments.
In the eighth minute, Esso's shot from over 20 yards missed the target, moments before Gibril Sillah hit a free-kick wide at the other end.
Ghana came close to breaking the deadlock in the 29th minute when Shafiu's shot from outside the box deflected off an opponent and crashed into the crossbar.
A minute to half-time, Konadu's outfit was presented with another scoring opportunity but Anabila's hit, having found a loose ball inside the box, went just wide.
Shortly after the interval, Ghana went close once again, this time when a Gambian defender's attempt to clear away Moro Ibrahim's cross almost sent the ball into his own net. Goalkeeper Ebrima Jarju reacted quickly to force a save which saw the ball first hit the woodwork and fly over for a corner.
In the 66th minute, the Black Stars finally broke the deadlock through Esso who beat his marker to prod Ibrahim's cross into the net from close range.
Gambia almost levelled the score 10 minutes later but Ghana goalkeeper Eric Ofori Antwi was well positioned on the line to coolly collected Matarr Ceesay's diving header from close range.
There was more misery for The Scorpions in the 82nd minute when Modou Cham failed to convert a penalty after Alhassan was adjudged to have fouled his marker in the box.
Both teams had a few more chances to put the ball in the back of the net late in the game but their wastefulness in front of goal left the score at 1-0.