Video: Best of the Sprint Hurdles
Kendra Harrison dealt the first blow on the Road To The Final, beating Brianna McNeal in Doha. It would prove to be the starting gun on a season long duel between the two athletes, with McNeal winning in Shanghai, Stockholm and Rabat before clinching victory by a whisker in the Final.
Harrison, though, once again enjoyed a triumphant return to London, the scene of her world record breaking 12.20 two years previously, beating McNeal at the London Stadium.
In the men's 110m hurdles, Sergey Shubenkov defended his title with a fine 12.97 in Brussels, building on earlier victories in Lausanne and Monaco.
It was a close run thing, though, as Shubenkov came in just a stride or two ahead of 2016 Diamond Trophy winner Orlando Ortega. Both the Spaniard and Ronald Levy also took one victory on the Road To The Final, and that wasn't the extent of the competition. Not for the first time, Omar McLeod demonstrated some formidable early season form with wins in Shanghai and Eugene.