Eilidh Doyle, a contemporary and a medallist at Rio 2016, was in tears. She wasn’t the only one.
Muir’s second place in the 1500 metres in Tokyo’s Olympic Stadium will go down as one of the great moments of these Games, and a Scottish sporting achievement for the ages.
Her race lasted less than four minutes but it was a decade in the making. That’s how long Muir has worked with Andy Young, the coach who has helped her develop to the point where she can beat athletes of the calibre of Sifan Hassan, the Ethiopian-born Dutch runner who was a third of the way towards her stated aim of three golds in Tokyo. That target now needs readjusted.
The emotion she showed in her post-race interview showed just how much it meant to Muir.
Already a European champion indoors and out, this was her finally announcing herself on the global stage, fulfilling all that extraordinary potential.
Near misses at past Olympics and world championships can be consigned to history because this was Muir elevating herself to the status of track icons such as Liz McColgan and Allan Wells.
It was a great day for Team GB, a great day for Scottish athletics, but it wasn’t the only highlight of a fantastic Friday.
Katie Archibald and Laura Kenny teamed up to take gold in track cycling’s first-ever women’s Olympic Madison, the pair winning after 120 laps of thrilling, dangerous racing.
It was a second career Olympic gold for Archibald and a fifth for Kenny, who is now the most successful female cyclist in Games history and Britain’s most decorated female Olympian.
Archibald’s Scottish Cycling stablemate Jack Carlin won bronze in the men’s sprint and there was also a bronze medal for Borders hockey player Sarah Robertson who scored as Britain beat India 4-3 in an epic third-place play-off.
With a gold in the modern pentathlon for Kate French, Team GB are fourth in the medal table.
To put in perspective, Britain are ahead of Australia who have equalled their most successful Games of all time. Heady days indeed.