Louise Evans from business advisors Grant Thornton says promotion could be worth up to £150m for the club and will have knock-on benefits for the city and Wales.
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Details of the road closures and train delays ahead of Ed Sheeran's concert over the next four evenings.
Temperatures will not be quite as high as the last few days but it will still feel warm in the sunshine.
There will be a fresher feel with temperatures falling lower than on recent nights.