OAKLAND -- They have relievers stacked a mile high, enough to crowd the colossal Coliseum, and the A's had to use most of them after inverting their pitching plan Saturday.
But opening the game with a reliever -- the just-recalled Liam Hendriks -- in front of originally scheduled starter Daniel Mengden proved disastrous for these A's, their 14-man bullpen torn apart in an 8-7 loss to the Mariners that overshadowed home run No. 40 from Khris Davis, who joined Jimmie Foxx as the only players in A's history with three consecutive 40-homer seasons.

Using an Oakland-record nine pitchers in as many innings and falling just short of a comeback, the A's experiment cost them in the standings; an Astros win over the Angels yet again distanced the A's 2 1/2 games from first place, while their lead over the Mariners for the second American League Wild Card spot slipped to 4 1/2 games.
• A's add 8 to expanded roster
"We'll always re-evaluate and see what we think is best," A's manager Bob Melvin said. "Obviously we didn't get off to the greatest start."
The playoff-hopeful A's, venturing into September with an injury-ravaged rotation, were attempting to implement a blueprint designed and successfully utilized by the Rays, who debuted what has been deemed the "opener" on May 19 against the Angels, when they used veteran righty Sergio Romo to pitch the first inning.
So there was Hendriks, at one point this season designated for assignment by the A's, toeing the rubber as Mengden lingered in the bullpen. A scoreless first inning was something of a tease, though, after Hendriks put two on with two out in the second, forcing Melvin to play matchups not one-half hour into this marathon.
Lefty Danny Coulombe, also promoted to join Oakland's expanded roster on Saturday, was quickly tagged for a two-run double off the bat of Ben Gamel. Then came Emilio Pagan, who picked up the final out ahead of Mengden's entrance.

This form of bullpenning, as the Rays devised, stems from the premise that starters struggle going through a lineup three times. Yet Mengden, who was knocked around while getting little help from a sloppy defense, didn't even get through it twice, needing 54 pitches in two innings. The right-hander was on the hook for four runs (three earned) and five hits, before the bullpen resumed action.
"I'm here to do whatever I can to help the team win, so if that's after an opener coming out of the bullpen, then that's what it's going to be," Mengden said. "It's different, it's unique, and I feel like baseball is evolving, doing new things, trying new things, and if it helps the team win, it helps the team win. Just one of those things, small sample things. Can't really judge if off one night."
Newbie Cory Gearrin had a tough time, too, surrendering two runs when taking his turn, leaving the A's scurrying to play catch-up. They did their best, getting a two-run homer from Mark Canha in the fifth and solo shot from Davis in the eighth ahead of Marcus Semien's bases-clearing double opposite closer Edwin Diaz to make it a one-run game.

Jed Lowrie opened the ninth with a walk off Diaz, who promptly struck out the side.
"Pitching early on wasn't great but later on we shut them down, gave ourselves chances, then had the winning run at the plate," Melvin said. "Continued to fight and put ourselves in a position to potentially win."
MOMENTS THAT MATTERED
Looking to limit the damage in the third inning, Mengden induced a weak fly ball off the bat of Ryon Healy, only to watch it drop among an A's contingent in shallow right field. Moments later, Kyle Seager sent a sharp single to right field, and Denard Span, who planned on holding up at third, came in to score when second baseman Jed Lowrie fumbled the relay throw, contributing to a lengthy inning for Mengden.

SOUND SMART
The A's used 24 players in all, setting an Oakland record for players used in a nine-inning game. The previous mark was 22 (Sept. 28, 2003 at Seattle).
YOU GOTTA SEE THIS
Davis' eighth-inning blast was naturally of the opposite-field variety, his specialty. The slugger regained the Major League home run lead with a shot off right-hander Alex Colome to jumpstart a four-run eighth inning. It was his first homer since Aug. 23.
"Pretty amazing," Melvin said. "He's been stuck on 39 for a little bit. I think that happened maybe the first year or two. Now he's past it. It's just miraculous numbers that he puts up. We've had a long history of power hitters here, and to be with Jimmie Foxx and that kind of company, and we're still looking at close to a month left, he's been as consistent a power hitter as anybody who's been in Oakland."

HE SAID IT
"It's going to affect the routine a little bit, but you gotta adjust to it. Something that little shouldn't be that big of a deal. It's a little different sitting down in the bullpen for an inning or two, but I gotta be ready for anything and make adjustments on the fly." -- Mengden
UP NEXT
Right-hander Edwin Jackson, who is 4-3 with a 3.03 ERA in 12 starts with the A's, will toe the rubber Sunday in opposition of Mariners righty Felix Hernandez (8-12, 5.49 ERA). The finale of this four-game series at the Coliseum is scheduled for 1:05 p.m. PT.