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.
More top news
Tuesday lunchtime's weather for the west for the region
Tuesday lunchtime's weather for the east for the region
Work officially begins to decontaminate nine areas of the city which experts believe traces of the agent still remain.