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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Manali Lukha has the latest weather forecast for the east of the Meridian region.
Manali Lukha has the latest weather forecast for the west of the Meridian region
A man is due to be sentenced at Truro Crown Court this afternoon for carrying out an acid attack on a man in a case of mistaken identity.