SEATTLE -- For the Mariners, this weekend’s series was always going to carry a little more hype, a little more fanfare and a little more weight.

The defending World Series champs are in the house, and they look even better than they did last year. There’s less than one month until the postseason, and far more eyes are on Seattle than in recent memory with the increasing likelihood of the Mariners ending their playoff drought.

For all these reasons, this weekend is a barometer. Atlanta is every bit the type of heavyweight that the Mariners will see night in and night out in October, and they were awakened to how sizable that challenge will be in a 6-4 loss on Friday night.

“Atlanta, they have a great team. They’re one of the best teams in the league,” said Carlos Santana, the veteran leader who’s been on three playoff teams and who crushed two homers on Friday. “They’re doing the same things as us, trying to make it to the playoffs.”

The Mariners entered play with an .816 winning percentage in games in which they scored four or more runs, but that production wasn’t enough on a night when their pitching staff -- which has been as dominant as any the past two months -- looked more vulnerable than usual. Robbie Ray and Matthew Festa surrendered two homers each, marking just the seventh time all season and first time since Aug. 1 that the Mariners have given up four in a game.

Seattle’s bats punched back with three deep flies, a solo shot from J.P. Crawford and the two from Santana -- including a monster blast that caromed off the top deck in right field. But on a night when Ray wasn’t as crisp and labored to 95 pitches in just five innings, then Festa gave up a leadoff homer to Michael Harris II and another to Robbie Grossman, Seattle was basically playing from behind all evening.

“They made him work,” Mariners manager Scott Servais said of Ray. “He was close to 100 pitches there through five innings. It's not typically what we've seen out of Robbie. He's been really consistent getting us deep in ballgames. They swung the bats well against him.”

Ray had been so dominant entering Friday, riding a 13-inning scoreless streak spanning two outings against AL Central-leading Cleveland, and he was the AL Pitcher of the Month for August.

Yet, Atlanta proved to be an ominous opponent, entering the night ranking second in homers (206), OPS against lefties (.808) and slugging percentage against fastballs (.508) -- all strengths that were on display.

“They're a tough team,” Ray said. “They can grind out at-bats, even when they're not getting on base, the guys, they can put a good AB on you. So it's a tough lineup, but I’ll flush it and move on to the next one.”

Nine of the 17 balls in play against Ray were hard-hit (95 mph or higher), his third most in a start this year, and he was regularly behind in the count, with first-pitch strikes to just 12 of his 24 batters.

Ray struggled to locate his two-seam fastball to righties, which led to a solo homer by Travis d’Arnaud, and the lefty admittedly left his slider in the zone at times when he didn’t intend to, which led to a two-run shot by Dansby Swanson.

“With the slider, I just need to be a little more cognizant of when the strike slider is good and it’s going to play and when I need to throw it below the zone for a swing and miss or a chase,” Ray said. “I feel like sometimes I get them backwards. ... I think execution was maybe a little off today. This is a good-hitting team. You can’t really be off against them. They’re a deep lineup.”

Defensively, the Mariners improved from an uncharacteristic showing that led to Wednesday’s loss. Yet, one wide route taken by left fielder Jesse Winker in the fourth led to a run after Harris was able to leg out a double then later score on Grossman’s single.

Pregame, Servais said that in order to beat the Braves, “You’ve got to play a good game, you’ve got to make the plays defensively. They've got young players that are very athletic.” It was forecasted that such plays would manifest.

“They’ve got a good team. We have a good team,” Servais said. “They beat us tonight. But we're going to have to make a few adjustments.”