A week after victory over Ireland lifted them back into the Top 10 of the rankings, Ioan Cunningham’s side have climbed another place as a result of their 24-19 win over Scotland in a Cardiff Arms Park thriller.
With just over three-quarters of a rating point riding on the outcome, Wales move up to eighth on 73.63 points with Scotland dropping down to ninth on 72.72 points.
In what was a great advert for the women's game, Scotland belied their underdog status to race into a 19-7 lead at the start of the second half after Lana Skeldon’s early score was followed by a brace from Rhona Lloyd.
But buoyed by the support of a record 4,875 home crowd, Wales responded strongly with Sioned Harries, Kelsey Jones and Ffion Lewis adding to Carys Phillips’ earlier try.
Wales then withstood a fierce late onslaught from the visitors to hold on for a victory that makes them the higher-ranked of the two teams.
The win will also give Wales the psychological edge ahead of their Rugby World Cup 2021, played in 2022, Pool A encounter against Scotland in Whangarei on 9 October.
With France seeing off Ireland 40-5 and England completing a 74-0 victory over Italy in the other round two games, there were no further changes in the rankings.
Lydia Thompson was the star of the show with a hat-trick as the Red Roses recorded their 20th consecutive win.
England remain the world’s number one team on 96.26 points, while France stay third on 88.43 points.