MINNEAPOLIS -- With commissioner Bud Selig and several Twins greats in town to celebrate the 2014 All-Star game coming to Target Field, it was Samuel Deduno that stole the show.
The normally wild Deduno (5-2) struck out a career-high nine with no walks to help the Twins snap a seven-game losing streak against Seattle and win for just the fourth time in their last 20 games overall.
"Today I came out aggressive with all my pitches," Deduno said. "Fastball, changeup, curveball. Everything was working today."
After Trayvon Robinson singled with one out in the first inning, Deduno retired the next 18 hitters, all but one on groundballs or strikeouts.
"Their guy was really good today," Mariners manager Eric Wedge said. "He had an incredible breaking ball and he had a feel for it."
Plouffe gave the Twins a 5-0 lead in the fourth with his 20th home run and first since returning Aug. 13 after missing 21 games with a sore thumb.
Josh Willingham hit a 432-foot shot into the second deck in left field an inning later, his 32nd of the season.
The offensive outburst had manager Ron Gardenhire in a jovial mood. He gave credit for all the hits to Twins legends Rod Carew, Paul Molitor and Tony Oliva -- in the stadium for the All-Star game announcement -- standing next to Minnesota's bats before the game.
"I saw the bats shaking before the game. Then we started getting hits," Gardenhire said. "So all we have to do is have a Hall-of-Famer stand next to our bat rack before every game now and we'll be locked in."
Before Wednesday's longballs, the Twins had just one home run in their last 11 games.
It didn't get any better for Vargas as Justin Morneau drove in a run later in the fourth before Plouffe and Willingham went deep.
Vargas failed to finish five innings for his second straight start. He allowed six runs on eight hits over 4 2/3 innings, making him 0-2 with an 11.42 ERA in his last two outings.
"I didn't feel like I was struggling to make pitches," Vargas said. "Obviously they had some things go their way and were able to capitalize on them, but I didn't feel like I was struggling to make pitches. It's just too bad it went their way instead of ours."
The loss was just Seattle's fourth in its last 14 games and snapped a 16-game winning streak against teams under .500.
Deduno entered the game with a 37-to-30 walk-to-strikeout ratio, but didn't walk anyone for the first time all season.
Seattle's hitters flailed at the lanky right-handers curveballs in the dirt and couldn't figure out how to elevate Deduno's darting fastball.
"It was one of those days where you just don't know what it is," Robinson said. "Me, I was trying to swing at a strike and he was in the zone, but he had pretty good movement today. Tip my hat to him. He did a good job."
After winning his first four decisions, Deduno had lost his last two, including an ugly outing in Texas last week where he allowed 11 hits and seven runs in five innings.
After managing just two runs and nine hits through the first two games of this series, Minnesota broke out with 16 hits and its highest run total since scoring nine against Detroit on Aug. 13.
"I think tonight is what we're capable of being and doing as a team," Plouffe said. "We just haven't done that consistently all year. The good teams do that consistently."
Seattle was marching back to the .500 mark before being cooled by Deduno. It was the first time the Mariners have been shut out since July 15 at Texas.
Twins LHP Scott Diamond dropped his appeal of a six-game suspension for throwing behind Josh Hamilton and being ejected in a game against the Rangers last week. Minnesota announced Diamond's decision one day after he allowed five runs in seven innings of a loss to Seattle. ... Mariners manager Eric Wedge said OF Michael Saunders likely will return from a growing strain on Thursday after missing five games. ... An MRI on Denard Span's sore collarbone area showed that the Twins' outfielder has a sprained SC joint. Span was originally hurt on Aug. 12 and has only played four games since. "I guess we're going to take it kind of day to day. It's going to be painful, and it's going to be based on how I feel," Span said. "There will be days I can go out there and swing and there will be bad days." ... Minnesota recalled 1B Chris Parmelee from Triple-A Rochester and outrighted RHP Jeff Gray to Rochester. ... Seattle's Blake Beavan faces Brian Duensing in Thursday's series finale.