RIO DE JANEIRO – Kristin Armstrong of the United States won her third straight Olympic time trial Wednesday, a golden effort through wind and rain over a brutal course that left her in an exhausted heap at the finish.

Armstrong dismounted the moment she stopped the clock, too tired even to celebrate the latest triumph of her decorated career. She covered the Rio Games route in 44 minutes, 26.42 seconds to top reigning bronze medalist Olga Zabelinskaya of Russia by the slimmest of margins: 5.55 seconds.

Anna van der Breggen of the Netherlands added a bronze medal to her gold from the road race.

Armstrong, who turns 43 on Thursday, joined speedskater Bonnie Blair as the only American women to win three gold medals in the same event at any Olympics. She also won in Beijing and London.

Dutch rider Ellen van Dijk slid off the wet road along the southern coast of Rio de Janeiro and finished fourth, the miscue likely costing her a medal. Road race bronze medalist Elisa Longo Borghini of Italy was fifth and world champion Linda Villumsen of New Zealand sixth.

Despite her pedigree, Armstrong was a controversial selection for the U.S. team.

She retired for a second time shortly after the London Olympics, then decided earlier this year to pursue a third gold medal. But she eschewed competing in the toughest races in Europe to spend more time with her family, much to the chagrin of rival riders who made the sacrifices of racing abroad.

Then there were the accusations of bias: Her longtime coach, Jim Miller, also directs the national team for USA Cycling, though he recused himself from all deliberations over her selection.

Ultimately, two Americans filed for arbitration to try to make the team. One of the riders had beaten Armstrong in the national championships, putting her place on the team in doubt.

It wasn’t until a week before she departed for Brazil that Armstrong’s place was confirmed.

Her latest gold medal was almost certainly her toughest.

She led by nearly 5 seconds after 10 kilometers but had dropped 3 seconds behind Zabelinskaya by the second time check. She made up the difference over the final flat run to the finish, precisely the kind of terrain that suits her riding style perfectly.

Zabelinskaya was also a controversial figure coming into the race.

The Russian tested positive for the substance octopamine in July 2014 and accepted an 18-month ban, and that doping violation was poised to keep her from the Rio Games when the International Olympic Committee set in place rules that barred Russian athletes for previous doping offenses.

Last week, the Court of Arbitration for Sport ruled the IOC’s rules were “unenforceable.”