China's Guo Wenjun retained her women's 10m air pistol title in a thrilling final at the Royal Artillery Barracks.
Guo, 28, was the leading qualifier but made a slow start as Celine Goberville of France built a lead.
Going into the last of the 10 rounds, Goberville was 0.5 ahead but could only produce an 8.8 with her final shot and Guo's 10.8 gave her victory on 488.1.
Goberville was level on 486.6 with Olena Kostevych of the Ukraine but took the silver with a 10.6 in a shoot-off.
BBC Sport commentator David Oates's analysis
That was a nerveless display, a 10.8. Guo Wenjun saved the best until last. She's been under a lot of pressure and was widely considered the favourite. Though her score was not quite up to Beijing, any gold medallist who retains an Olympic gold is very, very special.
Guo, who did not reach the final of the Olympic test event in April, began with a modest eight, the lowest score in the first of the 10 rounds in the final.
It meant she was third overall, taking into account the one-point lead she carried forward from the qualifying round.
But a 10.8 with her second shot put her back in a share of the lead with Kostevych, the
gold medallist at Athens
but only 31st in Beijing four years ago, and Goberville, competing in her 11th final in 14 events.
Having led after the fourth round, Guo dropped back to third in round six following a second successive 10.1 as Goberville moved ahead.
Goberville's 10.6 extended her advantage to 0.8 over Kostevych and Guo with two rounds remaining.
However the Chinese shooter, whose total was 4.2 down on Beijing four years ago, showed great composure at the finish with her second 10.8 - only one mark below the best possible score for a single shot - to secure the gold.