New Zealand's Hamish Kerr wins Olympic men's high jump
Kerr and McEwen both managed bests of 2.36 metres in regular competition, but could not be separated on countback of missed jumps.
They opted for a jump-off, Kerr clearing 2.34m when the American failed after the bar was lowered from 2.38 to 2.36m.
There was a hint of deja vu at the Stade de France as Qatar's Mutaz Essa Barshim had shared Olympic gold with Italian Gianmarco Tamberi in the Covid-hit Tokyo Games three years ago.
The discussion Kerr and McEwen shared with officials was short and to the point: both athletes wanted to continue, there was to be no shared gold.
When McEwen missed his attempt at 2.34m in the jump-off, world indoor champion Kerr had his chance and took it with aplomb.
Barshim took bronze with a best of 2.34m, but Tamberi had a night to forget, finishing 11th in the 12-strong field with a best jump of 2.22m.