The rule of fandom has always been this: When other teams’ players get suspended for PEDs, they are blatant cheaters, unworthy of any sympathy.

When ours get caught, however, they are good guys caught in a gaffe. So Carlos Ruiz’s 25-game ban for Adderall in 2012 was dismissed as just a screw-up in prescriptions. Chooch got a standing ovation upon return.

We give our players every benefit of every doubt. We forgive. Until Lane Johnson. The Eagles right tackle is about to be slammed with a 10-game ban for using performance-enhancing substances — his second penalty in three years. And this time, very few Eagles fans trust that Johnson is that solid citizen tripped up by mere carelessness or a rigged system.

Johnson crawled from his fox hole of shame last weekend to blame everyone but himself for his poisonous pee test. His union which, he said, “doesn’t support players.” The supplement-screening app provided by that union, which carries several disclaimers he chose to ignore. The manufacturer of the mislabeled junk he bought online. Hey, who’d ever imagine that something purchased on the internet couldn’t be 100 percent trusted?

This is an old song for Lane. He never totally manned up the first time he was suspended for PEDs in 2014. He blamed poor performance on Eagles fans in 2015, saying, “It’s not really a home field advantage playing here anymore.” He was the first player to rip Chip Kelly after the coach’s dismissal. I didn’t disagree with much of what Johnson said at that time, but thought it ungraceful of him to rush out with a shovel to bury the man who made him the fourth-overall pick in the draft.

Johnson has never quite played up to that lofty draft position. But the Eagles believed in him enough this offseason to give him a six-year deal with a $35.5 million guarantee. With Jason Peters’ career fading, the 26-year-old Texan has been slotted in as the anchor left tackle of the future.

Forget that for now. Whether Johnson knowingly cheated in this instance or just got caught in a case of blatant stupidity, his impending suspension is about the worst news the Eagles could get.

Carson Wentz’s cracked ribs are a bummer for fans who wanted to see his development this preseason, and it’s compounded by the reality that we’ll now have to watch more Chase Daniel. But Wentz won’t be starting on Sept. 11 regardless, and wasn’t part of any vague hope that the Eagles might actually be competitive this season.

Lane Johnson was among the most important players expected to take the field for the opener. Now, the right tackle will be Allen Barbre or Dennis Kelly or another overmatched body. And with Peters already rickety, the Eagles' offensive line projects to be worse than the inept quintet from last season.

The Vegas over/under for Eagles wins stands at 7.5. From this viewpoint, sitting here in mid-August, Lane Johnson just made the “under” seem inevitable.