In the past eight days, they have made Safeco Field unsafe for visiting teams.
"One thing we talked about is that we need to protect our house," said manager Lloyd McClendon. "We had not been very good at home."
Heavy on the past tense.
With a 6-3 victory against the Toronto Blue Jays on Tuesday night, the Mariners have won seven of the first eight games on a homestand that is arguably the most important for this franchise in the past two decades, in light of the fact that the season is in its final stretch and a postseason berth is at stake.
OK, this isn't 1995, when the future of the franchise in Seattle was at stake, but it's more demanding than when the Mariners spent 141 days in first place in 1997 or 2001, when they won a best-in-baseball 116 games.
Just how big a homestand has this been, particularly the series against a Blue Jays team that arrived ahead of them in the American League Wild Card race, but now find themselves two games back?
Well, in order to push Felix Hernandez back a day to start the series opener against Toronto on Monday, the Mariners optioned lefty Roenis Elias to Triple-A Tacoma, even though he has been one of the surprising constants in the rotation, and they called up Erasmo Ramirez. In the Sunday start against the White Sox, Ramirez responded with 4 1/3 shutout innings in what became a 4-2 Seattle win.
It's been that kind of a roll for the Mariners.
With a game against Toronto on Wednesday to finish out the homestand, Seattle has a winning record at home (33-32) for the first time since the third home game of the season.
The Mariners have moved into a virtual tie with the Tigers for the second AL Wild Card spot, with 43 games remaining in the regular season.
They are still getting strong efforts from the pitching staff. They have put together streak of 11 consecutive games in which they have held the opposition to three runs or fewer, lowering their season ERA to 2.97, well below the club record of 3.54 set in 2001, and putting them in position to become the first AL team with an ERA below 3.00 since the 1974 World Series champion A's.
Now, however, they also are getting an impressive offensive display. After hitting .235 and averaging 3.3 runs per home game the first four months of the season, Seattle has hit .285 and averaged 6.2 runs in its past eight games, which included the Mariners' two-game sweep of the Braves, taking three of four from the White Sox and back-to-back wins over the Blue Jays.
So what's so different?
Well, the lineup, to start with.
"We were talking in the bullpen about the changes we have made and how we are a way better team right now," said reliever Joe Beimel. "The lineup has become quite a bit better. It's more balanced. It's got a veteran flavor."
The first four months of the season, Seattle was running out left-handed-heavy lineups, even against left-handed pitchers. In the final days of July, however, general manager Jack Zduriencik answered his peers who complained he was tough to deal with by working three trades that helped right the Mariners' ship.
First came the acquisition of switch-hitting designated hitter Kendrys Morales from the Twins on July 24. Then came the pickup of Chris Denorfia from the Padres early on July 31, the date of the non-waiver Trade Deadline. And then came the addition of leadoff-hitting center fielder Austin Jackson in a three-team deal with the Rays and Tigers in which the Mariners only parted with Minor League shortstop Nick Franklin.
Now comes the payoff, in terms of production, but also in terms of a veteran influence.
"The lineup change has been part of it," said left fielder Dustin Ackley, "but we also are learning how to win. Everybody is starting to click at the same time."
There's Robinson Cano getting the protection of the veteran Morales in the lineup. There's Jackson, a participant in the past three postseasons with Detroit, providing stability in center field and at the top of the lineup. And there is the versatile Denorfia, capable in all three outfield spots.
There also was the arrival of shortstop prospect Chris Taylor, who has hit .375 in his first 16 big league games, and the emergence of Ackley, a .323 hitter since the All-Star break, 98 points better than his pre-break average.
"Again," said McClendon, "our lineup is better. We have a better chance of winning than we did three weeks ago. We have a better balance. We have more of a veteran influence."
And that has come without impacting the pitching staff, which has compiled a 1.97 ERA in the past eight home games, well below what was an impressive 3.06 home ERA the first four months of the season, when the Mariners were a concerning 26-31 at Safeco.
"The pitching staff lets everybody be comfortable," said Ackley. "When we are deep in the game, we know there's a good chance we are going to win."
That, however, isn't a surprise.
That has been the feeling since Opening Day. It's the lineup that has become a factor.