The two left-handers shared a second-wicket stand of 175 and although opener Joyce was out shortly after reaching his 11th one-day hundred 21-year-old Machan, who was playing only his third List A game for Sussex, pushed on to score an undefeated 126.
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Friday night's forecast for the west of the region
It's a Bank Holiday weekend, with half term for many. Here's how it's looking on the roads, in the skies, and at getaway hotspots