Faith Kipyegon ran the mile of her life today. And yet the 31-year-old Kenyan, the best female middle-distance runner of all time, failed to add a new line to the history books, by running six seconds shy of becoming the first woman to run one mile in under four minutes.

Kipyeon ran four laps of the Stade Charléty track in Paris in 4 minutes, 6.42 seconds. The audacious attempt came with the help of sweeping support from Nike, which worked with Kipyegon on every aspect of the run, including designing her a bespoke running suit and track spikes. The company dubbed the attempt Breaking4.

Faith Kipyegon missed the mark by about six seconds. World Athletics would not have recognized a record because the race wasn’t sanctioned, live competition.