The 19-year-old diver from Burghfield Common won silver in the men's 3m springboard final in Tijuana, Mexico, with a personal best score of 436.74.
The second placing gave them their first World Series medal as a pair with the Chinese duo Kai Qin and Yutong Lou occupying top spot.
In the diving World Series in Moscow earlier this month, the pair came fifth in the men's 3m springboard final.
Back in February, the Commonwealth finalists won bronze in the FINA Grand Prix in Russia with a score of 416.46.
They are steadily improving having only worked together for less than a
Their attention will now switch to securing Team GB places for the London 2012 Olympics at the British Championships in Sheffield from June 8-10.
* See next week's Chronicle for an exclusive interview with Chris Mears.