BOSTON -- If the Red Sox are going to become a true contender, they are going to have to start beating some.

After losing two straight to the Phillies -- capped by Wednesday's 5-2 defeat at Fenway Park -- Boston is seven games behind the Rays for the second American League Wild Card spot with only 34 games left.

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While you can't pinpoint one thing for what has been a disappointing title defense so far, it is definitely surprising that the 67-61 Sox are 23-37 against teams with a winning record.

"Today was just not good baseball," said Red Sox manager Alex Cora. "Overall, it's been what we've been throughout the season, the ups and downs of being inconsistent. I've been saying all along, for us to get to that streak that we've been talking about from the get-go, we've got to be more consistent."

The roster is very similar to the one that won the World Series last year, but the results have been markedly different.

"A lot of good ballclubs out there and we're having a tough time getting on a roll and making up the ground we need to make up in the Wild Card or division, whatever, to get our foot in the door," said losing pitcher Rick Porcello. "There's no hanging heads or anything like that. You keep pushing forward, but yeah, it's been really frustrating not to be able to get on a roll this year."

In what has become a recurring theme this season, a brief tease of momentum -- this time a five-game winning streak -- has been stalled by two straight losses to a contender.

"We got hot for five days or whatever," said Cora. "Yesterday was a good game overall. But today, we made some mistakes. With teams like that, you can't do that."

Like all the other contenders who have come into Fenway this season, the Phillies were revved up at the opportunity to go toe to toe with the defending champions.

"I remember what it's like to play here and how difficult it is for a team to come in here, the middle of the summer, playing the defending world champions," said Phillies manager Gabe Kapler, who was part of Boston's curse-breaking World Series team in 2004. "More specifically, it's one of the best lineups in baseball and something that we were really paying close attention to."

The good news for the Red Sox is that their next nine games are all against sub.-500 teams. Perhaps that will give them a chance to get hot again before the Twins and Yankees come to Fenway for a seven-game homestand that starts Sept. 3.

The starts and stops have been frustrating.

"It's been going on all year, honestly," said Porcello. "We've had a hard time getting on a roll, extending winning streaks and series and winning series and doing that for a long time. It just hasn't happened for us. It's not for a lack of effort. It's not for a lack of focus. That's the game."

It was a night that started with promise, as Rafael Devers belted an RBI double off the Monster in the first and Jackie Bradley Jr. went deep for a solo shot in the second.

Porcello had a 2-0 lead, but he couldn't hold it in the top of the fifth. The most damaging hit was a two-run shot by Bryce Harper, who teed off on a misfired 1-2 slider by Porcello and put it into the Monster Seats to give the Phillies the 3-2 lead.

"Yeah, it was supposed to be backdoor," Porcello said. "Got him out on the first at-bat and he put a good swing on it. It was a little bit lower than we'd like to throw it. We were in a good, favorable count and we had some options that we could have wasted some pitches, see if he'd chase, do some different things. We went with that and he got it. It was a good swing. Just needed to be a better pitch."

This one was hardly all on Porcello, or the bullpen for giving up two insurance runs after his exit.

The offense didn't do any damage for the final seven innings. In the fourth, the Sox had bases loaded and one out, but they didn't score. It was part of a frustrating night in which Boston left nine on base, as the lack of situational hitting continues to be an issue.

Though the offense has been one of the most productive units in the Majors when it comes to overall numbers, the Red Sox are 3-49 when they trail after six innings.

"Actually, me and [hitting coach] Timmy [Hyers], we were just talking about that," said Cora. "It seems like we have expanded the zone a little bit. Usually we hunt pitches in the middle of the zone, and when they're there, we do damage with it, and we stay away from the edges.

"It seems like the last, what, 15 days, it seems like we're doing that. We go over reports and everything, we prepare the same way we've been doing it for a year and a half or more. Right now, it seems like one of those ruts. We should be better than what we're doing right now."

And if things don't change soon, the team that owned October last year won't be playing during that month this year.