We were arguing among ourselves in the media seats about the last time two teenagers had fought so closely for Olympic gold medals on the track
In the end Athing Mu decided the matter anyway, the American lording the women's 800m from the gun, which began with an opening lap of 57.9 seconds; fast, very fast.
Britain's Keely Hodgkinson bided her time close to the back, only there was no stopping Mu, who kicked again off the front down the home straight and took gold in a US record of 1:55.21 while Hodgkinson took silver in 1:55.88, breaking Kelly Holmes' British record,
“I thought it would be really tight going into the first 400m,” said Mu. “You can use your head, but you have to run your race, be ready to execute. That is what I did. If nobody was going out there I was going to do it myself.”
Later Elaine Thompson-Herah from Jamaica became the first woman to successfully defend a sprint double at the Olympics.
“It’s been a rough week,” said Thompson-Herah. “I’m super tired, I hardly slept after the 100m. My legs really need a rest now because we ran two rounds of the 200m in one day yesterday, which isn’t normally the case. To run a national record, I’m so, so happy.”
Anita Wlodarczyk, already the finest women's hammer thrower of all-time, added another stunning superlative to her career when she became the first woman to win three Olympic titles in the same event. As in any event.
As expected Mondo Duplantis was the last man standing in the pole vault as he landed his first senior global title.
The world record-holder didn’t record any failures up to and including his winning height of 6.02m.
“It’s a surreal feeling, I don’t know how to explain it,” said Duplantis. “It’s something I’ve wanted for so long, and now I finally did it. It’s so crazy.
“It is overwhelming. Ever since I was a little kid, I’ve loved the sport so much. This sport has given me so much, I can never repay it. My father and mother have been so instrumental in my success; the fact they’re able to be here today [as my coaches] makes it even more special.
Earlier Andrew Coscoran advanced to the semi-finals of the 1,500 metres after a positively determined run.
Biggest competition
"It doesn't always go right, at the right time," said the north Dublin runner, who with that gave credit to coach Feidhlim Kelly.
“We got it right, we’re fit, we’re here, we’re fresh. We’re ready to go. We wanted to put ourselves in the mix, and we did. We’ve raced a lot, got good at racing, did the European circuit, there was no being soft, We just kept driving on.
"Nick Willis [the New Zealand runner who also qualified] said to me in the warm-up, 3:37 would get us through, and he went and ran 3:36 obviously. My coach [Feidhlim] said get in behind him, or Jakob, latch on to them, and I got it done. Let them to the work for me."
Sporting a magnificent green harp tattooed under the top of his left arm, Coscoran added: “This is the biggest competition you’re ever going to run, so if you’re not nervous there is something wrong with you. But I calmed the system down, got real tactical about it.
“It’s semi-finals now, and there is no one more dangerous that someone who has nothing to lose. I’ll go out there and give it a lash, see what happens. For me, the more races I do back-to-back, the better I can, Maybe the semi-finals is the race to that.”
Later in the evening, Irish sprinter Leon Reid also made it through to the semi-finals of the 200m, where he finished seventh in 20.54. Earlier in the day Phil Healy, competing in her third event in Tokyo, fell just short of a place in the semi-finals of the 400m despite running a season best of 51.98 seconds.
