Defar, the 5,000m gold medallist at Athens 2004 and London 2012, pulled away to win in a world-leading time of 8 min 30.83sec.

The Ethiopian had not competed for more than two years with the birth of her daughter in 2014 and injuries in 2015 keeping her off the track.

"I didn’t have the confidence to push hard in the middle of the race after so long away," said the 32-year-old.

"Now, after the race, I feel my confidence rising."

The United States’ Abbey D'Agostino finished a distant second behind Defar with a time of 8:56.77.

Her compatriot Natasha Hastings broke the American women’s 300m indoor record, crossing the line in 36.25 at the Reggie Lewis Center.

Hastings, a member of the US’s Olympic gold medal-winning 4x400m team at Beijing 2008, bettered the mark of 36.33 set by Allyson Felix in 2007.

Another American, Boris Berian, won the 600m with an event-record and world-leading time of 1:15.51, which is the second-best US finish ever and fifth best in history.

New Zealand’s Nick Willis ran a world-leading 3:53.27 to win the mile, and 19-year-old Ethiopian Dawit Seyaum took the women's 1,500m crown in a year best 4:01.86.

The US’s Kurt Roberts won the shot put with a world-leading mark of 21.57 metres, despite still recovering from a back injury that limited him last year.

Olympic champion Jenn Suhr triumphed in the women's pole vault at 4.82 metres but failed in an attempt to push her world indoor record to 5.07m.

The American’s two-week-old mark stands at 5.03m, just shy of Russian Yelena Isinbayeva's 5.06m world outdoor record.

In the men's pole vault, world outdoor champion Shawn Barber of Canada was upset by American Sam Kendricks with the former jumping 5.67m and the latter 5.77m.