Boston had the same result in Anaheim and will bring an 0-6 mark -- not to mention a season-high six-game losing streak -- into Seattle, the third and final leg of the journey.
The Sox have been outscored, 54-15, in the six games.
"It's not easy," said right fielder Cody Ross. "We're professionals. We have to come back from being down. That's the name of the game. At the end of the day, we have to score more than they do. We just have to keep fighting. It's unacceptable."
Though the Red Sox haven't played particularly well in any facet of the game in recent days, starting pitching has been the element that has betrayed the team the most.
Daisuke Matsuzaka was the latest Boston starter to have a short and unsuccessful stint. The righty lasted only 3 2/3 innings, giving up seven hits, six runs and two homers.
He was the fourth Sox starter in the last five games to pitch less than four innings.
The disappointing performance came on the heels of a strong performance by Matsuzaka at Fenway Park last Monday, which, by the way, was the last game that Boston won.
"I was really disappointed in myself, especially as I knew I had to pitch deeper into the game, especially knowing how much the bullpen has been used in recent games," Matsuzaka said through interpreter Jeff Cutler. "I knew they needed a break. All I wanted to do today was pitch like my last game, pitch as long as I can, one batter, one inning more, but I couldn't do that. I'm really disappointed in myself."
On the road trip, the starting rotation is 0-5 with an 11.52 ERA.
The Red Sox have also been forced to play from behind in all six games, leaving the offense out of sorts.
With the trade of Adrian Gonzalez to the Dodgers and the continued absence of David Ortiz and Will Middlebrooks, the last thing the Boston can afford to do is play from a significant deficit.
"We don't have the firepower to keep climbing out of big holes early," said manager Bobby Valentine. "It's a tough way to make a living."
How tough has this trip been for Valentine?
"What difference does it make?" Valentine said after his team fell to 62-73.
Considering the current roster makeup, there's been even more burden than usual on star second baseman Dustin Pedroia. But he has risen to the challenge. A three-hit day on Sunday increased his hitting streak to 13 games. Pedroia had a .370 average during that stretch.
"I'm impressed with him every day I've seen him since the first day I've seen him," said Valentine. "There's nothing like him. He's a very special player."
But numbers have never meant nearly as much to Pedroia as winning, which is why this is probably the lowest he's felt in his career.
"Yeah, it's tough," Pedroia said. "We're not playing good baseball by any means; we're really not doing anything well, so we just have got to show up at the yard, get yourself prepared and come out and play as hard as you can."
Sunday got off on a down note when Matsuzaka opened the first by walking Coco Crisp and then gave up a two-run homer to Seth Smith.
Dice-K didn't give the Red Sox any scoreless frames in this one. Stephen Drew drilled a one-out solo shot in the second.
The A's sent eight batters to the plate in the third, scoring twice. Josh Reddick got one home with a sacrifice fly and Drew's RBI single made it 5-0.
Matsuzaka again got into trouble in the fourth, as the A's loaded the bases with one out. Yoenis Cespedes increased Oakland's lead to six on a fielder's-choice grounder. That was the last batter Matsuzaka faced, as Andrew Miller came out of the bullpen.
"When you're playing well and you score a couple runs first, everyone has that good feeling again that things are going to work out on that particular day again," said A's manager Bob Melvin.
The A's and Red Sox couldn't be going in any more opposite directions, as Oakland extended its winning streak to nine games.
Stifled by Brett Anderson over the first five innings, the Red Sox at last produced a rally in the sixth. Jose Iglesias started it with a walk. With one out, Scott Podsednik and Pedroia singled, loading the bases. Ross lined a single to left, which had mixed results for the Red Sox. Pedro Ciriaco scored, but Podsednik was cut down at the plate on the throw from Cespedes.
Now it's off to Seattle where the Red Sox are desperate to have something good happen.
"Nobody's quitting," Pedroia said. "We're professionals. We're going to play as hard as we can, [but] this isn't a 'trying' league, you've got to go out and play well and win the game, and we haven't done that."