In Madrid on Friday evening, Isaac Makwala ran a historic 200m and 400m double at the IAAF World Challenge meeting.
The 30-year-old became the first man ever to run a sub-44 400m and sub-20 200m on the same day.
In the 400m, the Botswana athlete ran a sub-44 time for just the second occasion in his career, clocking 43.92.
It was the third fastest time of the season behind Fred Kerley's 43.70 and world record holder Wayde van Niekerk's 43.60.
Remarkably, just 75 minutes later, Makwala ran the fastest 200m of the season. The 30-year-old destroyed the field as he ran a new personal best of 19.77. It was also a national record.
The time bettered the previous world leading of 19.84 set by Wayde van Niekerk in Jamaica last month.
The battle between him and van Niekerk at the World Championships should be an interesting one.