RSL has been good enough at home, but it’s a horror show on the road. Why?

Real Salt Lake’s game results paint a stark contrast: a four-match winning streak at home and a five-match losing streak on the road.

The only matches that broke the mold were the first two of the season, a 1-1 draw at Dallas and a 5-1 loss to LAFC at Rio Tinto Stadium.

“When we do something, we do it big, I guess,” Real Salt Lake coach Mike Petke said after Saturday’s 4-1 loss at Philadelphia. “We don’t sit back, we don’t do this. We get opened up because we try to apply pressure, and what’s the difference between a 1-0 loss and a 4-1 loss? Three goals, but it’s still a loss.”

The differences in play at home and away, however, are much more subtle than the resulting scores. A little bit of an edge — a familiar field, the energy of a home crowd, playing a man up — has been enough for RSL to pull out wins. But without it, RSL has been unable to execute.

RSL’s home wins can be broken into two categories: strong performances while up a man (against D.C. United and Colorado), and close battles (Vancouver and New York Red Bulls).

The same can be said for the away losses. RSL put together promising performances in back-to-back road games at Vancouver and Orlando, only to concede late goals. Last weekend, however, instead of building on that progress, Real Salt Lake had another ugly outing in Philadelphia. Its biggest issue was team defending.

Real Salt Lake has conceded the most goals of any Western Conference team (25). Montreal is the only team in the league that’s allowed more, by two goals. Conventional wisdom attributed RSL’s defensive woes to a young, and even more important, inexperienced back line. However, at Philadelphia, veteran center back Marcelo Silva returned from a groin injury, and right back Adam Henley started at his natural position for the first time this season. Brooks Lennon, who had started the previous eight matches at right back, rejoined the attack at winger.

“It doesn’t really matter who’s in there,” said RSL television analyst Brian Dunseth. “At times the team — individually and collectively — the team’s defending in a pretty naive capacity. This isn’t a coaching thing, just to be very, very clear. This is players sorting it out on the field.”

In RSL’s bad stretches the club looks disjointed, with no connection between the back four and the attack. Such was the case last weekend.

“We worked on building out, we worked on trying to be aggressive, and there was just too much space,” RSL midfielder Albert Rusnák said of the problems against the Union. “If the front four and five decided to go and press, then the back five had other things on their mind and they stayed, and then Philadelphia found the pockets around us and they used the space well that we left.”

The issue has been compounded when central midfielders Kyle Beckerman and Damir Kreilach both dropped back deep, almost creating a six-man back line.

“In an ideal world you want to look at your No. 6 and your No. 8 as staggered,” Dunseth said. “And when they’re playing next to each other, that means right now that the opposite team is really, really overloading.”

When teams do overload, sending their outside backs up the line along with their wingers, RSL’s central midfielders either defend the run inside or help out wide. Either choice can be, and has been, exploited. Then even when RSL does win back the ball, it doesn’t have the choice to play it through the midfield on the counterattack.

“We need to be very compact,” Kreilach said, noting that it was something they had been working on in training. “This is the most important thing in soccer because on offense we need also to [play] defense. … Our lines need to be tighter.”

RSL carries Petke’s attack-minded philosophy on the road, rather than sit back and force a draw. That was an approach that worked beautifully for Real Salt Lake in the second half of last season.

Considering RSL’s results on the East Coast, Petke said he and his staff were considering taking a more conservative approach heading into Philadelphia. In the end, they decided against it.

“Looking back on Vancouver and Orlando, we put them on their heels and we had some success for 70 minutes of the game,” Petke said. “And so for us it was about waves in this game: the right opportunity to step up and press versus the right opportunities, when it’s a bit out of our reach, to get back into our shape.”

RSL couldn’t put that game plan into practice. Without any simple fixes on hand, RSL travels to Seattle this weekend. After that, it plays five of the next seven matches at Rio Tinto Stadium.