With Joe Mauer on the disabled list for an extended period, production has been well off the usual pace for the regulars, but the Twins unloaded 16 hits on a quintet of A's pitchers, with Justin Morneau leading the way.
Struggling with a .245 batting average, Morneau socked just his second home run - a two-run shot - of the season in the third inning, and also singled, doubled and scored twice in the rout.
At 15-27, the Twins still have the worst record in the AL, and remain 11 1/2 games behind Cleveland in the Central division.
Giambi belted three home runs and drove in all of the Rockies' run in a 7-1 victory at Philadelphia.
A three-run shot in the first was followed by two-run homers in the 3rd and 5th innings, as the Rockies earned a split in their brief, two-game series with the front-running Phillies.
Colorado continues to dog the Giants in the NL West, who remain 1/2 game in front of the Rockies after defeating the Dodgers, 3-1.