The Braves are concerned about Julio Teheran, a 2014 All-Star whose ERA has risen to 5.07. They should also be concerned about history: Teheran is the fourth young starting pitcher of the past five years to author what seemed a breakthrough season only to recede.

Jair Jurrjens was 25 when he made the 2011 All-Star team; he was an ex-Brave by 2013 and has started three big-league games since. Tommy Hanson, then 24, was 10-4 with a 2.44 ERA over the first half of the 2011 season; he was traded to the Angels for Jordan Walden in November 2012 and hasn’t started in the majors since Aug. 7, 2013.

At 25, Mike Minor was 13-9 with a 3.21 ERA in 2013. He went 6-12 last season. He hasn’t pitched in 2015 and underwent season-ending shoulder surgery in May.

Now Teheran, who’s 24 and who over his first two full big-league seasons had an ERA of 3.03. In 63 starts in 2013 and 2014, he had two games in which he yielded six or more earned runs; in his past eight starts, he has yielded six-plus earned runs three times.

Granted, there are differences in each case. The greater point, however, cannot be swept aside. An organization rebuilding around young pitching hasn’t seen a promising young starter turn into a full-blown ace this century.

“It’s not even the ace thing,” said Will Carroll, an Indianapolis-based writer who has written extensively on pitching and injuries. “It’s the fact they haven’t come up with even a No. 4 starter. Go down the list and (their touted young starters) have become injured or ineffective.”

Then this: “They’ve been good at finding them and getting them to (the major-league) level. They’ve had super prospects — they get there, and then they break. It seems to narrow the field (of culpability). I don’t like to point the finger from outside, but everything’s pointing to Roger McDowell.”

Some Braves fans will regard this as heresy. Over nine seasons, the Braves under McDowell have ranked among baseball’s top six teams in ERA seven times. But now another gifted young pitcher is struggling, and even manager Fredi Gonzalez conceded Wednesday that “we have talked internally about the comparison of Jurrjens and Teheran.”

Let’s be clear: Gonzalez swears by McDowell. (So did Bobby Cox.) But can we ascribe the ongoing failure of a Braves to turn big-time prospects into big-time pitchers to bad luck?

“It’s hard (for a pitcher) to maintain and sustain at the major-league level that high standard,” Gonzalez said. “I don’t know how to answer that question, to be honest with you. Minor is just injury. Hanson had a shoulder and a back. Jurrjens had a knee.”

And Teheran? “Teheran is just a matter of the league making adjustments, and he’s got to make an adjustment. There’s no health issue there. He still has velocity. He has to make an adjustment to the league.”

About velocity: According to Brooks Baseball, Teheran threw his four-seam fastball above 93 mph in 2013. Over the first two months of this season, it seldom broke 92 mph. (It has ticked up in his past three starts.) Jurrjens and Hanson saw similar dips; Minor did not.

Said McDowell: “Jair had an injury with his knee that progressed to where it was difficult for him to push off. Tommy had the shoulder issue. There are some factors involved that limits the level of success (a pitcher) will ultimately get to.”

Then: “At the end of the day, it’s about taking that young pitcher, making him feel comfortable, understanding that he’s going to make mistakes, understanding that as a pitching coach and as a staff (we need) to be there when those mistakes happen.”

The journeyman Aaron Harang said last season that McDowell was the best pitching coach he’d had at finding a hitter’s weakness. That could explain a bit of this. “The expectation of that (young) pitcher to execute a game plan as a Tim Hudson or an Aaron Harang would can’t be as high,” McDowell said.

Given that the Braves began Wednesday with a rotation of five men under 25 — Mike Foltynewicz was later demoted to Gwinnett — McDowell isn’t working with any Hudsons or Harangs. As the Braves venture further down the rebuilding road, there aren’t apt to be many graybeards along for the ride.

Is McDowell the right coach for what this team is becoming? He believes so. “Every day we come to the ballpark thinking, ‘What can we do to help that young man get better?’ Whether it’s Foltynewicz who has less than 10 starts or Julio who has had less than 100, there’s still process involved.”

Gonzalez: “I do believe he’s a pretty well-rounded pitching coach. … I trust Roger. He cares about the pitchers. He cares about what they do. He’s good at breaking down a hitter, attacking a hitter’s weakness. And I think he’s better than what people say mechanically.”

Carroll: “It’s not like they’re failing to develop a certain kind of pitcher. It’s every kind of pitcher. They’re just bad at developing pitchers.”