The 32-year-old McPherson booked her place on Jamaica’s team to this summer’s Tokyo Olympics when she won the quarter-mile in 49.61s that made her the fifth-fastest woman in the world this year. It was also the first time in eight years that she was dipping under 50 seconds in the event.

Not too far behind was newcomer Candice McLeod, who was making her first Olympic team, with yet another personal-best time of 49.91s. Roneisha McGregor also ran a personal best of 50.02 for third and will also race as an individual in Tokyo.

On a morning when several other athletes produced lifetime bests, it was McPherson’s performance that perhaps the most surprising. Before Sunday, the last time she broke 50 seconds for the 400m was in 2013 when she ran a then-personal best of 49.92 in Monaco. She also ran 49.99 in the final of the 400m at the World Championships that year that won the bronze medal.

Since then, the closest she has come was in 2016 when she ran 50.04 at the national stadium in Kingston in July.

This past offseason, she said, she made changes. She began working on her speed and focusing on her health more than she had before. The work to get her speed up, have seen her times have come down.

Since 2015, McPherson has had respective 200m season-best times of 23.19, 23.12, 23.12, 23.02 and 24.12. This year, her best time over 200m is 22.90.

“The fact that I am faster contributed to today’s (Sunday) performance,” she told Sportsmax. TV.

“Also, I have been working on my technique which has improved a lot. There are a lot of things that contributed to today’s (Sunday) performance or even me being a faster Stephenie. I live like a sprinter and I have gained a lot of weight and strength in the gym. So that’s one of the reasons why I am faster.”

She also revealed that a specific focus on avoiding injury has helped her make the kind of progress she has been denied for such a long time.

“The fact that I was able to stay healthy. That was my biggest problem. I was able to stay healthy this year because I went to the doctor for monthly evaluations,” she said, indicating that the extra effort allowed everything to come together nicely.

“The race plan was to just run even 200s and the fact that I am faster I was able to do that,” she said while revealing that during Sunday’s final she was not aware of anyone else in the race.

“At no point in the race did I see or feel anyone, I was so focused on my lane,” she said.

She closed by saying she had no intention to rest on her laurels before the Olympics.

 “There is still a lot of work to do and I still need to get faster,” she said.

The men's 400m was equally dramatic if short on quality as Sean Bailey held on for a close victory in 45.03 ahead of Christopher Taylor 45.13 and Karayme Bartley 45.17. 

Demish Gaye, the previous national champion finished fourth in 45.30.