The opening session of the World Athletics Relays in Gaborone produced two world records inside the same hour on Saturday, with Canada and then Jamaica trading the mixed 4x100m mark in successive heats and Jamaica becoming the first country to break the 40-second barrier in the event. The Jamaican quartet of Ackeem Blake, Tina Clayton, Kadrian Goldson and Tia Clayton crossed the line in heat three in 39.99, reaching the line a long stride clear of South Africa. Canada had set the previous mark of 40.07 in heat one, lopping more than two-tenths off their own 40.30 from Guangzhou twelve months earlier.
The relay was run for only the third time at this championship under the new running order — man, woman, man, woman — and the change rewards teams that can stretch the second leg into a long carry. Tina Clayton, fresh from her Jamaican 100m title, took the baton from Blake in the lead and held it through the back straight before exchanging clean to Goldson on the third leg. Tia Clayton ran the anchor unchallenged, gliding through the line as the stadium clock froze on a time nobody had reached on a championship track before. Both teams ran into a slight headwind under floodlights, lending the marks added authority.
Canada's run earlier in the evening had been the headline result on its own. The team, anchored by Sade McCreath after legs from Andre De Grasse, Marie-Éloise Leclair and Aaron Brown, had used the second mixed leg to build the kind of advantage that has eluded Jamaica in past combinations. The 40.07 was Canada's third world record in the discipline in three editions, and a national-team coaching staff that had spent the build-up emphasising continuity over star power got immediate vindication. The team had to wait barely twenty minutes to see it taken off them.
The qualifying picture beyond the mixed 4x100 also clarified for Beijing 27. Top-two finishers in each heat across the women's and men's 4x100, mixed 4x400 and women's and men's 4x400 booked their automatic places at the World Championships in late August, with the next two on time picking up the remaining slots. Botswana, racing on home soil, advanced from heat one of the men's 4x400 and the home crowd carried the team through the curve. Italy, France and the United States all came through on the women's side, while Belgium and South Africa renewed their well-rehearsed rivalry with Botswana over the longer relay.
Sunday's finals carry the marquee billing. The men's 4x100 line-up sees the United States, Jamaica, Canada and South Africa renew the sport's most-watched relay, and the men's 4x400 final brings Botswana, the Belgian Borlée family and the United States together for what is expected to be one of the meet's defining races. World Athletics will hand out a prize fund of over half a million dollars across the two days and the qualifying spots booked here will set the entry list for Beijing in late August. Two world records before lunch on Sunday is the bar; the second day starts with everyone trying to clear it.