Cardiff banished their blues after failing to reach the quarter-finals of the Heineken Cup for the first time as they blitzed Glasgow to consolidate their place in third position in the Welsh/Scottish League.
Despite having to withstand considerable pressure in the first-half against a strong wind, the blue and blacks hit back with a try on the stroke of half-time to cut their deficit to two points.
Glasgow could only muster three penalties by their outside half Graeme Kiddie with the wind at their backs and as soon as Williams skipped over for his try, which Nicky Robinson converted, the game was always in their grasp.
Three more tries flowed in the second half, from Matt Allen, Gary Powell and Francois Mounier, and Robinson added two conversions and a penalty to give the home side a much needed boost with a 29-12 victory.
For Glasgow it was only their third defeat in eight games, although things are likely to get harder for them when the Six Nations comes around and puts added pressure on their leading players.
Meanwhile, at Virginia Park, Sonny Parker took the starring role as Pontypridd continued their climb up the table with a 36-16 victory over Caerphilly.
Parker ran in two of his side's three tries. Fijian outside half Nicky Little helped himself to 21 points for the visitors.
WRU TV were on hand at the launch of a major new commercial deal with WRU and Mercedes-Benz South Wales (part of the Sinclair Group), which sees the family company become an official supplier to the Welsh Rugby Union
On the back of the recent Women's Rugby World Cup, the WRU has launched a revitalised Women's and Girls domestic seasonal structure, and the future is looking bright.
Go to www.wru.co.uk/tryourgame for more information
Roger Lewis talks to WRU TV at the announcement of a new £60 million Rugby Services Agreement (RSA) which provides a new and positive contractual relationship between the WRU and its four Regions for the next six years has been agreed.
The Welsh Rugby Union has announced a major new sponsorship deal with Gullivers Sports Travel which will make the UK's leading, and longest established, multi-sport tour operator, an Official Supplier for the rest of the decade.
Having taken part in seven World Cups as a player and coach, Liza Burgess hopes to go out in style this afternoon when Wales take on Australia in the Play-off for seventh and eighth place in the Women's Rugby World Cup in Paris.