The game, held in Istanbul after an original match between Turkey and Uzbekistan had been cancelled, saw Burak Yilmaz and Umut Bulut net for the hosts before Ghana captain Gyan pegged them back with a brace after coming on as a half-time substitute.
The hosts named a strong XI as they prepare for next month's FIFA World Cup qualifiers against Romania and Andorra, which they must win to keep their faint hopes of a play-off berth alive.
Kwesi Appiah made seven changes from his previous side that beat Lesotho in a World Cup qualifier in June, with former Milan striker Dominic Adiyiah playing up front.
Yilmaz opened the scoring after just seven minutes, pouncing on a loose ball as Ghana failed to clear Arda Turan's corner, slamming home from eight yards out.
The Galatasaray forward went close soon after, hitting an effort wide when one-on-one, but Bulut did double the advantage, with a near-post header from Hamit Altintop's centre.
Just 16 minutes after his introduction at the break, though, Gyan halved the deficit with a thunderbolt.
Picking the ball up in the left channel, the Al Ain man drifted towards goal, before unleashing an effort from wide past Volkan Demirel at his near post.
And the Ghana captain was to thank as they drew level. Daniel Opare swung a deep ball from the right flank, which Gyan powered home with his head.
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