The Pirates have reduced the deficit to nine points at the break. Aaron Penberthy gave them a fourth minute lead with a drop goal.
Rob Cook kicked a penalty, and it was his storming run in the 23rd minute that set up Matt Evans for the only try of the half, which Cook then converted.
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It will be a breezy start, with clouds arriving around lunchtime. The afternoon will be sunny with showers.
Tuesday will start dry and bright with lighter winds, before cloud thickens bringing some outbreaks of rain through the afternoon.
The day's gusts will ease as the evening goes on. It will be mostly dry with cloud cover but occasional clear spells.