The Seattle pitcher won his ninth straight decision at Safeco Field, throwing 6 1-3 effective innings Sunday as the Mariners beat the Oakland Athletics 6-1.
Saunders is 3-0 with an 0.94 ERA in four home starts this year, but is 0-4 with a 12.54 ERA on the road.
"It's killing me," Saunders said. "I know I have it in me, it's just a matter of doing it on the road. Hopefully we can turn the page a little bit and get a good start on the road."
In 13 career appearances at Safeco, Saunders is 9-0 with a 1.72 ERA.
"I don't think that's going to keep up. It's kind a fluky trend here early on," Seattle manager Eric Wedge said. "He's smart, he has a good feel, his stuff's been really good. I've been impressed with his stuff, so I don't think that's going to continue."
Saunders (3-4) allowed one run and five hits, striking out six and walking three.
Kendrys Morales gave Saunders an early cushion with a three-run homer in the first inning, and the Mariners kept adding more.
Tommy Milone (3-5) lost his fifth straight start, giving up five runs, six hits and three walks in five innings. This was the first time during the skid he failed to pitch into the seventh inning, and he has a 3.62 ERA over that span.
Milone walked two in the first more than he had allowed in all but one of his seven previous starts this season.
"I was maybe trying to be a little too fine in the first inning," Milone said. "Just tried to paint the black and that's probably what caused me to get behind."
Defending AL West champion Oakland has lost six of seven. The A's start a series Monday at division-leading Texas.
"You go through ups and downs, but this is not very fun now," said Oakland's Brandon Moss, who struck out four times.
Morales hit his fourth home run of the season in the first, a drive into the Oakland bullpen in left field that followed Michael Saunders' leadoff single and Kyle Seager's one-out walk.
"Kendrys came up with a huge hit and kind of got the ball rolling. Three runs in the first is kind of setting us up for a big game," Michael Saunders said. "We continued to keep adding runs throughout the game, and it was a great team game today."
Josh Donaldson and Luke Montz hit consecutive doubles in the second, and the A's had runners at the corners with no outs when Nate Freiman grounded to shortstop Brendan Ryan, who threw out Montz at the plate. Saunders retired the next two batters.
"Not too many shortstops make that play," Wedge said. "His awareness out there is tremendous. It would be a tough double-play the way the ball was hit."
Joe Saunders was as surprised as anyone when Ryan threw home.
"He about took my head off," Saunders said. "It was a heads-up play, he made a great throw and great tag."
Seattle stretched its lead on Jesus Montero's run-scoring single in the fourth and Seager's sacrifice fly in the fifth. Jason Bay added his fourth home run in the seventh inning, a drive to center off Jerry Blevins.
"We're playing good baseball right now," Michael Saunders said. "We're doing all the little things right, and it's showing."
NOTES: Oakland manager Bob Melvin said OF Coco Crisp, on the DL with a strained left hamstring, may run the bases Monday. If it goes well, a Wednesday return for Crisp is "not out of the question," Melvin said. ... Wedge batted Seager third and moved Morales and Michael Morse both down a spot in the lineup, to Nos. 4 and 5. Wedge said the moves were designed to take some pressure off Morales and Morse. "I've seen them both chasing more than they should be chasing," Wedge said.