The young right-hander was in trouble from the get-go. The Mariners plated a run in the first inning when center fielder Coco Crisp misplayed John Jaso's liner, scoring Michael Saunders. Parker then allowed three hits in the second inning, the last of which -- a double by Brendan Ryan -- plated two runs.
"I made a lot of mistakes," Parker said. "I was not happy with it. It's kind of embarrassing, to be honest. Set the tone early. What you want to do as a starting staff is be effective and attack early, and I did the opposite tonight."
Though 41 of Parker's 94 pitches were outside the strike zone, A's manager Bob Melvin said he thought the pitcher's control was fine, and that he just fell off as his pitch count got high near the end of his outing.
For his part, Parker blamed his struggles on not making the right pitches in the right counts. Whatever the reason, the rookie was forced out of the game during the Mariners' three-run fifth inning.
Parker's rough start ended his streak of four straight outings in which he gave up one earned run or less.
"Just kind of one of those nights," catcher Kurt Suzuki said. "He's been so good for so many starts that you just kind of take things for granted that he's going to go out there and do that. This game's tough. He's a hard worker, and his stuff was there tonight. They just hit the ball."
The A's staff as a whole saw their streak of seven straight one-run outings ended as well, leaving the rotation one game shy of tying the 1966 Kansas City A's mark of eight consecutive.
It was the most runs that offensively challenged Seattle has scored since it tallied 10 on June 20 against Arizona.
On the other hand, Oakland's recent offensive struggles continued in a big way, as the team was held in check all night by Mariners starter Jason Vargas. The left-hander spun his first complete game since he did the same a year and a day ago, which also came against the A's at the Coliseum.
"He had a good changeup going, he pitches to both sides of the plate very well," Suzuki said. "He's a good pitcher. He's not going to throw 95, 96 [mph], but he sure knows how to pitch. He kept us off balance all night, moved it up and down, left and right, and out of the middle of the plate. He did a good job."
Right fielder Josh Reddick was responsible for Oakland's only run, knocking his 20th home run of the season in the first inning.
"I really didn't throw anything but fastballs and changeups other than a couple cutters to Reddick," Vargas said. "Their philosophy is to try to get you to wear down and get your pitch count up. I feel like if I can pound the zone early and force the issue, it hopefully takes them out of their game plan and forces them to swing earlier and not be so patient."
Reddick's hit -- which made him the first Athletic with 20 home runs before the All-Star break since 2006 -- and his solid defense were two of just a few bright spots for the A's, along with Travis Blackley's three-inning scoreless relief outing. Melvin said he wanted to give the left-hander some work so he wouldn't be so far removed from pitching when he makes his next start after the break.
In all, the night was a far cry from the A's exciting last three games. Put in a deep hole, they had no chance at yet another dramatic late victory, as their stay at .500 lasted just one day this time around.
"We haven't played a game like that in a while, where we felt like we were down early, had to get multiple hits to even get back in it," Melvin said. "It's just one of those games, but we're all right. We've been playing pretty well."