OAKLAND, Calif. — A change came to the Mariners on Sunday. And no, it wasn’t just the unfamiliar result of a win away from Safeco Field — although that wasn’t a bad thing for a team that had lost six straight road games.

The Mariners’ 11-1 trouncing of the A’s was certainly needed, coming after a series of roster moves that included starting center fielder Leonys Martin being designated for assignment.

With the rout, the Mariners salvaged one win in an otherwise regrettable series against a division foe with a weaker roster and improved their record to 8-12.

Seattle showed off its offensive muscle, banging out 11 hits, including a third-inning grand slam from Taylor Motter and seventh-inning three-run homer from Nelson Cruz. All of that run support made it easy for Yovani Gallardo to pick up his first win of the season, pitching 61/3 innings, giving up one run on four hits with a walk and seven strikeouts.

“Our at-bats were really good today,” manager Scott Servais said. “But I tip my hat to Yovani Gallardo. He did an awesome, awesome job today.”

But what transpired in the 12 to 14 hours leading up to Sunday’s win, and the message it sent, was far more significant. A major change to the roster, a switch in playing time and more moves to come in the following days signaled the end of patience for slow starts and underachievement.

The changes were set in motion in the hours after Saturday’s disappointing 4-3 loss. Most notably was the decision to bring first baseman Daniel Vogelbach up from Class AAA Tacoma and designating Martin for assignment to make room for him. The other roster move of calling up right-hander Chris Heston and optioning right-hander Chase De Jong back to Tacoma was a move of opportunity with De Jong throwing four innings on Saturday and being unavailable to pitch for at least four days.

The Mariners have 10 days to trade, release or outright Martin to the minor leagues (he would have to clear waivers for the Mariners to send him to the minors).

“It’s the do-good league,” Servais said. “I say it all the time. I’ve said it before. We want to have guys have good process and good at-bats and all that other stuff. But when it’s not happening, you have to look at how long has this been going on and where we are at. Expectations for our ballclub are very high, as they should’ve been. We talked about it in spring training. I thought we were ready for it and we haven’t played that well, on the road particularly, and we’ve got to pick it up.”

The decision to designate Martin — a stalwart and popular presence on last year’s overachieving team and emotional sparkplug during games — wasn’t painless. It left the Mariners’ clubhouse quiet Sunday morning with many players realizing that playing time and big-league roster spots can expire with poor play.

“It was not easy,” Servais said. “Those decisions are hard. I really like Leonys. He’s a big part of what we were doing. Unfortunately, it just hasn’t gotten going offensively.”

Servais gave Martin the news in his hotel room Saturday night, and the two men with a long professional history and a close relationship talked extensively about why this had happened and what might happen going forward. Martin was a favorite of Servais for his boundless energy and joy when it came to the grind of a season.

“It’s hard to see anybody struggle, but especially guys you are close to and you have relationships with,” Servais said. “I’ve known Leonys a long time. I was there the first day he was a Ranger when I worked with Texas. Things happen. It is a business, as much as it as a game. There does come a time where you have to produce.”

Martin wasn’t producing at even a below-average clip.

He was hitting .111 with a double, four steals and an anemic .172 on-base percentage and a .130 slugging percentage in 15 games. Swing changes to lower his hands in the offseason proved to be counterproductive. He struggled to find consistency in the spring and it carried into the regular season. Out of desperation and under urging from the Mariners, he tried to switch back to his previous swing at the end of the season-opening road trip in Anaheim. But that offered minimal results and the awful slump continued to crush his confidence.

With Guillermo Heredia playing well and Jarrod Dyson capable of playing center field, the Mariners decided to make a change. Since Martin was out of minor-league options, they had to designate him for assignment. Because he’s owed most of his $4.85 million contract this season, there is a chance that he could clear waivers and be outrighted to Class AAA Tacoma.

“If Leonys does happen to clear waivers, he goes to Tacoma, hopefully he gets it right,” Servais said. “Quite frankly, I think that’s what he needs — to go out and play for a while, get it right, get some confidence back. We could see him back here. I don’t want to write Leonys Martin off as being a Mariner. He very well could come back to us.”

The Pirates are rumored to be interested in picking up Martin to offset the loss of Starling Marte to an 80-game suspension. But they are unlikely to pick up his full contract. The Mariners could work out a trade with Pittsburgh and take on some of that money owed.

That Vogelbach was the call-up also changed up the playing-time parameters, meaning the experiment to play Danny Valencia as the everyday first baseman is over. With Valencia hitting .145 with a .443 OPS, the Mariners had to do something at first base. They will go back to their original pre-spring-training plan of using two first basemen. That plan was scrapped when Vogelbach struggled in spring training at the plate and in the field, forcing the Mariners to make a move.

“I just went through a little slump,” Vogelbach said of spring. “I was missing pitches that I shouldn’t have missed and when I was having good at-bats and getting the pitches I earned in that at-bat, I was missing them. When you miss pitches and get down in the count against the best pitchers in the world, it makes it really difficult on yourself.”

Vogelbach, 24, was inserted into the lineup at first base for Sunday’s game, going 1 for 4 with a walk and an RBI. He will play against right-handed starting pitchers. With the Mariners expected to face a slew of right-handed starters in Detroit and Cleveland, he will play extensively.

Vogelbach was hitting .309 (17 for 55) with three doubles, two home runs, 14 RBI and an .882 on-base plus slugging in 16 games with Class AAA Tacoma. Over his last 10 games, he’s hitting .351 (13 for 37) with two doubles, two home runs and 12 RBI.

“He’s going to play first base,” Servais said. “It’s the bat that we are looking for from him, understanding that he’s been swinging the bat very well in Tacoma, kind of doing what he does, he controls the zone, lots of deep counts. And that’s what we want him to do here.”

Heston will serve as a long reliever for the time being, but could go back to Class AAA Tacoma when Steve Cishek comes off the disabled list, possibly on Tuesday in Detroit.

The Mariners are also expecting shortstop Jean Segura to be activated from the disabled list, meaning another roster move will come.