The Orioles have the worst ERA in all of baseball at 5.20.

They have the second worst starting rotation ERA, 5.82, behind only a Cincinnati Reds’ group that has been decimated by injuries.

As bad as you may have thought last year’s pitching was – the Orioles were 19^th in the majors with a 4.22 total ERA and 24^th with a 4.72 rotation ERA – it’s much, much worse this year.

Historically awful, really. The Orioles have a chance tonight to become the first team in baseball history to allow at least five runs in 21 consecutive games.

The only major change in personnel from last season to this season has occurred within the coaching staff.

The five primary starters for this year’s team were in the rotation last year. The same goes for much of the bullpen.

So, the blame for this disastrous pitching stretch has to be on the shoulders of new pitching coach Roger McDowell, right?

Wrong.

“If someone’s gonna try to use him as a scapegoat, it’s the wrong tree to bark up,” Orioles manager Buck Showalter told me earlier this week.

And I agree wholeheartedly.

Yes, the pitching staff under McDowell and bullpen coach Alan Mills has regressed as a unit from the group that Dave Wallace – McDowell’s mentor — and Dom Chiti had last year.

But it wasn’t a particularly impressive group in 2016. We all knew that. The hope was that young pitchers Kevin Gausman and Dylan Bundy could take a step forward, Chris Tillman would be his steady self, Wade Miley and Ubaldo Jimenez wouldn’t stink and the stout bullpen would remain so.

The bullpen, however, has taken its lumps, primarily because unhittable closer Zach Britton has been hurt most of the year. Also, Darren O’Day has been injured through a chunk of the year, Brad Brach and Mychal Givens have been put in unfamiliar roles, Donnie Hart has stumbled in his sophomore campaign and the bevy of optional arms acquired to stop the bullpen bleeding have been an inconsistent tourniquet.

Is any of that Mills’ fault?

Of course not.

Yet McDowell is receiving heat. It’s been a topic of conversation multiple times among the powers that be that run the warehouse – that maybe a change is needed at pitching coach.

And that’s ludicrous. Not after three months with a seriously flawed rotation.

This isn’t an offensive coordinator calling plays in the NFL, people. This is baseball, when a coach can provide a pitcher with plenty of information, plenty of instruction, but that player has to execute with his own ability. McDowell can’t send in an ingenious double-reverse, and he can’t throw the baseball for these guys.

Can McDowell make Kevin Gausman command his fastball better or leave fewer fat pitches in the middle of the plate? Can he make sure that Chris Tillman is healthy, strong and mechanically sound once he toes the rubber? Can he make Wade Miley more consistent or Ubaldo Jimenez not a train wreck?

To an extent, I suppose. There are suggestions, there are tweaks, there is confidence to build and mountains of video to analyze. But, ultimately, the ball is literally in someone else’s hands.

If you want to point fingers, there is plenty of blame to go around.

It should start with the pitchers themselves, obviously. But, as the saying goes, you can’t fire all of them.

Then there’s executive vice president Dan Duquette, who put this roster together. He is the one who looked at a terrible pitching market this offseason and decided to go with what he had. He chose to believe that Gausman, Bundy, Miley and Jimenez would all be better than they were in 2016. Only Bundy is making a case there.

He’s also the one that didn’t make a move when it looked like team anchor Tillman wouldn’t be ready for the season. To be fair, most teams are pitching-thin, the free agent class was dreadful and the Orioles had no shot of putting a prospect package together that could come anywhere near what the Boston Red Sox gave up to land star left-hander Chris Sale. They tried; the conversation was short.

But Duquette does oversee the farm system that is void of true, blue-chip prospects, so that’s on him. And so are the myriad trades he has made over the past few years that shipped away several mid-tier pitching prospects that are, at the least, now big league options for other teams.

Duquette blanches every time his minor league system is criticized, and he points to several homegrown players currently thriving for the Orioles. And there is merit to that. But with the rotation drowning nearly nightly, there is only flotsam at Triple-A Norfolk — pitchers who may drift in and out of the big leagues, but no one who can stick now and buoy the rotation for years. The Orioles are hoping lefties Chris Lee and Jayson Aquino can flourish, but, based on their Triple-A numbers, they’re certainly not the answers now.

While we’re casting blame for this pitching mess, let’s not absolve Showalter completely. He is the manager, and wins and losses should be his barometer, at least to an extent. He also has more decision-making power than most field managers, and he undoubtedly has the ear of majority owner Peter Angelos. He’s in his seventh full season, and his pitching staffs have never been a strength. So, he’s not faultless here.

Angelos, of course, will always be blamed for the failings of his club. That’s his cross as the man with the final say. Yet I’ve stopped complaining about Angelos’ lack of spending. The Orioles are 10^th in the majors with a $168.7 million payroll, that’s plenty good enough to compete with and win.

You can certainly make the argument that Angelos has not spent on pitching. He’s never seen long-term, megadeal contracts for pitchers as a smart investment, and, history usually proves him to be correct. He amended club policy on not going beyond three-year deals for free-agent pitchers in 2014, when Duquette and company convinced him to sign off on a four-year, $50 million deal for Jimenez, which will go down as potentially the worst contract in club history.

If there is major fault with Angelos and his spending philosophy, it’s that the organization refuses to pay big bonuses to international amateurs — hitters or pitchers. Again, history has proven that can be a colossal waste of money, too. But the farm system is never going to reach its potential if one major avenue of talent procurement is almost completely ignored.

I guess my point in all of this is McDowell’s pitching staff is faltering at an historic level, but the root of the pitching problems goes way beyond McDowell, way above his salary grade.

Remember, McDowell spent his past 11 seasons as the pitching coach for the Atlanta Braves, including several years under managing legend Bobby Cox. During McDowell’s tenure, the Braves had the fourth best ERA in baseball. Surely all that success wasn’t simply because of McDowell, but it is one of the reasons he was hired by the Orioles.

“Bobby (Cox) said he’s one of the best he’s ever had. He said, ‘Buck, if he’s available, you better get him.’ He liked him, and that says something,” Showalter said. “I don’t think there is anybody that works harder at his trade than (McDowell). Before and after he got here. He’s done a good job. The pitchers, they think the world of him. He’s never wavered in his support of them. He’ll give them the tough love, too. I’ve been impressed with him.”

Showalter is exceptionally loyal. And he’s obviously going to defend his guy, his hire.

But the bottom line is McDowell can only do so much. Firing him three months into the season would be cosmetic, ceremonial. It wouldn’t solve any of the problems engulfing this pitching staff.

Duquette and Showalter have helped recover this organization from the ashes. That shouldn’t be forgotten, either. They deserve some rope here.

But they also are the ones that misjudged the quality and health of this starting rotation. That’s on them, not the new pitching coach.