A 70th-minute field goal by Cameron Smith lifted Melbourne over the defending champion North Queensland Cowboys 15-14 and into second place in the National Rugby League.
Smith's second career field goal came in the first half of a rare NRL doubleheader.
In the second match at Suncorp Stadium in Brisbane, the Broncos, second on the ladder before the match, moved just ahead of the Storm on points difference and into first place by pasting the Manly Sea Eagles 30-6.
The Sea Eagles agreed to a lucrative deal offered by the Queensland state government, surrendering home-ground advantage to the Broncos, who are undefeated at Suncorp this season. Brisbane ran in five tries to one to notch its sixth win in seven games.
Earlier, Tyrone Peachey had three tries and the Penrith Panthers scored 16 consecutive points in the second half to beat the New Zealand Warriors 30-18 .
Luke Keary scored a late try to give South Sydney a 22-20 win over Parramatta, and St. George Illawarra beat Canberra 16-12 in extra time on Euan Aitken's intercept try.
On Sunday, fourth-place Cronulla plays at Newcastle, and Wests Tigers play Canterbury in Sydney. Gold Coast hosts the Sydney Roosters on Monday.