Ramirez earned his second victory in his third start of the spring by giving up one hit and walking one while striking out four.
Ryan Vogelsong struggled in his first start of the spring after two relief appearances for San Francisco. He gave up seven runs (five earned) and six hits in 2 1-3 innings. He walked one and struck out two.
The Mariners scored four runs in the first on the homers by Miller and Saunders. Seattle added five more in the third, helped by a pair of Giants errors.
Dustin Ackley doubled and drove in two runs. He finished with three of Seattle's 18 hits.
Mariners: Ramirez appears ticketed for a spot in manager Lloyd McClendon's rotation, particularly if he keeps pitching the way he did Saturday.
"I concentrated on throwing strikes," Ramirez said. "I didn't want to go out and think too much. Everything was working good. The changeup was working. I was missing with the curve early, but I adjusted. ... My arm is getting stronger, and I am getting more control of my body."
Giants: In eight games before Saturday, members of the projected rotation had combined for 23 innings, allowing one run on 13 hits and three walks.
"It stopped big-time," manager Bruce Bochy said.
Bochy said Vogelsong, the team's No. 5 starter for now, had trouble spotting his pitches and left the ball up.
"The ball carried today, and if you get the ball up, the chances are that it's going to get hit hard," Bochy said. "Vogey needs to settle down and get his (arm) angle back. He's got about three more starts to get it worked out."
Giants: New left fielder Michael Morse did not play and likely will be out a few more games with a strained calf. Bochy indicated it is nothing serious.
Right fielder Hunter Pence is scheduled to play Sunday, but that might change depending on how he feels, Bochy said. Pence, who played in all 162 games last year, felt a twinge in his left elbow while swinging a bat.
ROMO ROUGHED UP AGAIN
San Francisco closer Sergio Romo had another rough outing against the Mariners.
Romo pitched the eighth inning but did not retire a batter, facing five hitters and giving up five earned runs and two walks. In four appearances covering three-plus innings, he has given up 12 runs (11 earned) and 11 hits.
"When he's good, he's hitting his spots on both sides of the plate, but he's off right now," Bochy said. "He hasn't thrown his slider much and wants to work on his fastball and get that right."
Bochy said he would talk more in detail with Romo about the situation.
Giants shortstop Brandon Crawford's wife had a baby at the hospital directly across the street from Scottsdale Stadium on Saturday morning.
The Giants have brought back one of their former outfielders for another opportunity. Darren Ford signed a minor league contract and adds a much-needed element of speed.
Ford was in the Giants' organization from 2008-11. He was with Seattle and Pittsburgh after that.