Moscon jumped away from a select group on the 3km final climb, finishing the 152.2km stage from Nanning to the Mashan Nongla Scenic Spot five seconds ahead of Felix Grossschartner (Bora-Hansgrohe) and eight seconds ahed of Sergei Chernetski (Astana). Carlos Verona (Mitchelton-Scott) was 11 seconds back in fourth, with Rigoberto Uran (EF Education First-Drapac) in fifth with the same time as Verona.
Stefan Küng (BMC Racing), Pascal Eenkhoorn (LottoNL-Jumbo) and Roger Kluge (Mitchelton-Scott) eventually broke away from the bunch after a contentious first hour of racing, and the lead trio built maximum advantage of 3:20 as the peloton and overall contenders waited for the 3km climb to the finish.
EF-Drapac led the chase for Uran, while Trek-Segafredo also helped to set-up Gianluca Brambilla. Quick-Step Floors also chipped in, with Davide Martinelli doing some huge turns on the front. Küng was the final survivor from the breakaway as the chase picked up in the final 15km, but he too was back in the fold at the base of the final climb.
Peter Kennaugh (Bora-Hansgrohe) tried an early attack, but Moson's move with 1km to go proved decisive, giving the 24-year-old his fourth win of the season.
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