Bulletin shows Welsh fans rampaging (9)
I believe the answer is:
newsflash
'bulletin' is the definition.
(I know that newsflash is a type of bulletin)
'welsh fans rampaging' is the wordplay.
'rampaging' is an anagram indicator.
'welsh'+'fans'='welshfans'
'welshfans' is an anagram of 'NEWSFLASH'.
'shows' is the link.
(Other definitions for newsflash that I've seen before include "Brief report" , "Dramatic announcement" , "Bulletin" .)