Millwood (2-4), who carried a no-hitter into the sixth, struck out seven and walked just one as the Mariners put the brakes on a four-game skid.
Millwood's last shutout came in 2003 when he was a member of the Philadelphia Phillies. The 37-year-old right hander threw three that season, including a no-hitter against the Giants on April 27 of that year.
"I felt like my stuff was good in the first couple innings of the game," said Millwood. "My location was pretty good and I felt like if I could keep my location where it was I had a chance to at least give us a chance."
Kyle Seager drove in a pair of runs, Mike Carp belted a solo homer and John Jaso had an RBI for Seattle.
Alex White (0-3) was pegged with the loss after giving up three runs -- two earned -- on seven hits over seven innings.
"My job is to keep the team in the game, get deep in the ball game and just keep us there and give us a chance to win in the end. That's what I tried to do," White said.
Seattle wasted no time and took a 1-0 lead in the first. Mike Saunders tripled and scored when Seager singled to center.
Carp made it 2-0 after a solo homer in the second, his third of the season.
The Mariners picked up a pair of insurance runs in both the sixth and ninth innings to go up 4-0.
In the sixth, Ichiro Suzuki singled, stole second and advanced to third when Wilson Rosario's throw sailed into center. Suzuki later scored when Seager lifted a sacrifice fly to left.
Seager opened the ninth with a triple before scoring two hitters later when Jaso flied out to left.
The Rockies finally had an opportunity to score in the sixth. With Marco Scutaro on first, Jordan Pacheo singled, but Scutaro was gunned down at third to end the frame.
Dustin Ackley had his 13-game hitting streak snapped...Seager and Ackley both played with the losing pitcher White in college at North Carolina. The trio took three trips to the College World Series in 2007, 2008 and 2009...The Rockies are 56-38 in interleague play since 2006.
05/19 02:43:54 ET
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