Spaniard Ruth Beitia leaped into the Rio night to win Spain's first Olympic gold medal in women's athletics and claim her first global outdoor high jump crown at the age of 37 on Saturday.

The three-times European champion cleared 1.88m, 1.93m and 1.97m at her first attempts and became the oldest Olympic champion in the jumps on countback when all four remaining athletes failed to get over two metres.

"I'm happy," she said. "Never did I think I'd be competing again after London. My dream has become a reality."

Mirela Demireva of Bulgaria took silver ahead of 32-year-old former world champion Blanka Vlasic of Croatia, who added bronze to the silver she won at the 2008 Beijing Olympics.

American Chaunte Lowe was the one jumper of the quartet who cleared 1.97m to miss out on a medal.

Like 32-year-old Lowe, Beitia was appearing at her fourth Olympics having finished 16th in Athens, seventh in Beijing and fourth in London.

She always looked like continuing her upward trajectory in Rio after clearing 1.88m with a minimum of fuss.

Beitia became the oldest medallist in the women's high jump by six years and was also a year older than Heike Drechsler when the German won long jump gold at the Sydney Olympics.