"A nice night, one to relax finally," Gardenhire said. "We've had a lot of close ballgames. But the boys swung the bats good tonight."
The victory also pulled the Twins to within a half-game of the White Sox for the American League Central lead. Minnesota gained a game after Chicago suffered an 8-0 loss at Boston earlier in the night.
The Twins offense had been struggling to score on this 14-game road trip, averaging just 3.0 runs over their last five games. But on Friday night, they broke out for a season-high 20 hits.
That was largely thanks to some big production by the middle of their lineup, including their Nos. 3 and 4 hitters.
Joe Mauer tied his career high with five hits in the victory -- a feat he accomplished once before on June 27, 2006 against the Dodgers at the Metrodome. His performance included a season-high four RBIs.
Justin Morneau added a four-hit performance with an RBI, which came when he delivered two hits in that six-run second inning. His 4-for-6 night that included two doubles brought his average to .313 on the season.
"An impressive night for our three and four hitters," Gardenhire said. "That's pretty much our offense. When they get going like that, we can be pretty good.
"They are probably the best 3-4 hitters in the league," A's manager Bob Geren added.
Mauer's 5-for-6 night at the plate raised his batting average to .324, retaking the AL lead in hitting. Although he's been consistent this season in his chase for a second batting title, Mauer said recently that he's lacked spectacular nights like the one he had on Friday.
So was it nice to finally break through and have a night like that?
"Over the last couple weeks, I haven't been feeling that great at the plate," Mauer said. "Today, I just tried to get back to the basics at the plate and go up the middle. It seemed to work out for me."
Mauer and the rest of the Twins got things working early. Facing A's starter Dan Meyer for the very first time, the Twins didn't allow the left-hander to stick around for long. Meyer (0-3) lasted just 1 2/3 innings, giving up six runs (two earned) on four hits.
It was Meyers' own throwing error in the second inning that was costly. After giving up back-to-back doubles to Morneau and Jason Kubel, Meyers' throw on a ball hit by Delmon Young to the mound pulled first baseman Daric Barton off the bag and allowed Young to reach base safely.
A walk by Brendan Harris loaded the bases and Alexi Casilla, in his first night in the eighth hole, hit an RBI single to center to make it a 2-0 ballgame.
With one out, Denard Span drew a bases-loaded walk for another run and, following Nick Punto's strikeout, Mauer added a big two-run single to center. Morneau capped off the scoring with an RBI single to right to make it 6-0.
"A lot of bloops, jam shots and that's what happens in nights like these," Gardenhire said of his offense. "Balls start falling in everywhere. They make good pitches, you hit 'em. They make bad pitches, you hit 'em. We've been on both sides of that. But a lot of good at-bats tonight and we took pitches early in the game."
The early-inning offensive outburst helped ease the load for Twins starter Kevin Slowey. The right-hander continued the string of strong starts for the Twins by allowing just two runs over his six innings, extending his winning streak to five games.
"It takes you a little longer to get loose," Slowey said of the long second inning by his offense. "But I'll trade that every time [for those runs]."
Facing Oakland for the second time in his last three starts, Slowey (11-8) made it two straight outings against the A's with double-digit strikeouts. Following up his career-high 12-strikeout game, Slowey struck out 10 on Friday night while issuing just one walk.
Oakland's lone runs came in the fourth inning on a two-run homer by Jack Cust. At the time, it cut the Twins lead to four, 6-2, but the Twins wouldn't let it stay that way for long. Minnesota added two more runs of their own in the fifth on Jason Kubel's sac fly and Brendan Harris' RBI single to center.
After so many nights of putting stress on their relief corps, the Twins were able to give their bullpen a comfortable lead. When Slowey exited the game, the Twins were leading, 8-2, and the offense only tagged on more runs from there.
Craig Breslow helped aid the blowout as he pitched three scoreless innings to earn his first career Major League save.
The victory brought the Twins' record on their 14-game road trip to 4-5.
More importantly, it gave the Twins a sense of confidence for their offense that really seemed to need a night like Friday.
"It's huge for us," Mauer said. "Over the last couple weeks we were pressing a bit. Hopefully we can get this momentum and keep it going."