With no fans to watch from the stands, four-time Olympic champion Mo Farah and Sifan Hassan both broke the rarely run one-hour world record.
In an empty stadium because of the coronavirus crisis, Hassan first improved the previous women's mark of 18.517 kilometres set by Ethiopia's Dire Tune at the Ostrava Golden Spike meeting in 2008 by covering 18.930 kilometres at the Memorial Van Damme.
In the final race of the meeting, which is part of the Diamond League series, Farah broke Haile Gebrselassie's 13-year-old record of 21,285 kilometres on his return to the track. Farah, who ran with his training partner Bashir Abdi, established a new world record of 21.330 kilometres.
"I'm very happy to break the world record today. What an amazing way to do it and to show people what is possible," said the 37-year-old Farah.
Hassan and Kenya's world marathon record-holder Brigid Kosgei fought toe to toe at the King Baudouin stadium. Hassan accelerated in the final minute to leave the marathon world-record holder powerless in her slipstream.