Jeremy Guthrie might be this season’s highest-profile meltdown of a pitcher new to Coors Field, but he’s not exactly the lone ranger:

Guillermo Moscoso had an earned-run average of 3.38 last season for Oakland, mostly as a starter. Obtained by the Rockies with Josh Outman in exchange for outfielder Seth Smith, his ERA was 8.23 in two big league stints before being returned to the minor leagues. It was 11.21 at Coors; 2.79 elsewhere.

Outman had a 3.70 ERA for the A’s last season. In his first year with the Rocks, that number is 9.00. He, too, has been returned to the minors.

Tyler Chatwood, obtained from the Angels for catcher Chris Iannetta, had an ERA of 4.75 in the American League as a 21-year-old. At 22, for the Rocks, his ERA is 7.62. Like the others, he is now a minor leaguer.

So it seems worth getting some insight into the specific difficulties pitchers face making their pitches in the less-dense air a mile above sea level. Unfortunately, when you go looking for big league hurlers who found a way to succeed at Coors and are willing to talk about it, you find it’s a pretty small group.

No one has taken the mound more often for the Rockies over the past three seasons than reliever Matt Belisle. He led the team in appearances two years ago with 76 and again last year with 74. This season he leads with 45 through 88 games, one back of the league leader, Shawn Camp of the Cubs. In a year in which the Rocks were determined to get Belisle’s appearances below 70, he’s on a pace for 83.

He also leads the club in earned-run average at 2.25, a number that was 1.88 before he was charged with two runs Saturday night against the Phillies. The previous two seasons he compiled ERAs of 2.93 (2010) and 3.25 (2011) — microscopic by Rockies standards. His splits this year are 2.92 at Coors and 1.54 elsewhere.

He wasn’t feeling great Saturday night after giving up two extra-base hits down the right field line in the ninth, but he was accommodating, as always. I started by asking if there are pitches he eliminates from his repertoire at altitude or pitches he relies on more at sea level.

“I guess the answer to that question is yes,” he said. “Do I eliminate? No. I know what happens to the spin or the bite, so to speak, on my off-speed pitches here compared to other places. The break size is going to be different. Sometimes the speed is different. So I’ve had to learn how to adapt my sights, my vision of where I’m releasing the ball, to make sure that I compensate for the lack of bite. So I guess what I’m trying to say is when we leave here, my rotation seems a little tighter and I get better snap on my pitches.

“All that means is I have to adapt and focus more on locating here and when I do mix speeds, to make sure that the arm speed’s there and the approach is extremely aggressive. When you’re feeling good with your spin, sometimes you can get away with sort of flipping one in there. You can’t do that here. That kind of got me in trouble tonight, actually.

“So I think it’s just an adaptability of focus. Is it a change? Yes. How significant it is I think is up to the person.”

Although Rockies pitchers tend to avoid talking about the effects of altitude publicly for fear of sounding like they’re making excuses, they do discuss it frequently among themselves. Complicating those discussions is the fact that altitude seems to act differently on each pitcher and each pitch. There are few rules that work for everybody.

“We’ve all talked about it in here,” Belisle said. “Some people have their arsenal change in similar fashions and some are a little different. So I think it’s up to the individual to really acknowledge what you have and what’s going on and just really focus on (keeping the ball) lower and understanding that the break will be a little different.

“Five out of seven of the guys in the bullpen may say their curve ball suffers, but two of them may say, ‘Actually my curve ball’s great; it’s my slider that has problems.’

“But that’s the same phenomenon as one guy can throw the exact same baseball and it feels like a bowling ball and the other guy, it feels light. It’s what he can do with the snap. So there is a change. It’s just something you have to adapt to.”

The modern emphasis on radar guns and computerized strike zones on television may give fans the impression that pitching is science, but it’s much more art. From one outing to another, a pitcher’s feel of his pitches may change dramatically. Altitude adds yet another variable.

Breaking pitches are more vulnerable because, lacking the velocity of the fastball, they sit up begging to be crushed if they lack their customary snap. But the lighter air can also affect the downward plane of the sinker, or two-seam fastball, leaving it, like the breaking ball, sitting up too high in the strike zone.

“It could be all of them, but I think everybody’s more affected with the breaking balls, the off-speed pitches,” Belisle said. “The fastball/sinker does change a little bit as well. Sometimes it may run instead of really corkscrew down.

“Then when you go on the road, you’ve got to kind of make sure and re-set because all of a sudden the bite’s a little more, so the same pitch that was a strike for my curve ball may be a ball if I’m throwing it at the exact same release point, so I’ve got to kind of change that.”

So you have a different release point at altitude than you do at sea level?

“Yeah, because my sight has to change. We’re talking very small.”

Is that a mechanical adjustment?

“Well, not so much a mechanical adjustment as it is the timing of when I release the pitch, when I say it’s a different release point.”

So it’s the same arm slot, but you may have to release the ball a little earlier or a little later?

“Correct. I may have to get rid of the ball a little later in Colorado and not even think about it so much on the road. But if I’m here for a week and then go on the road, while I’m playing catch, I’ll get a feel of, OK, that one was a strike in Colorado but now it’s a ball because it bit a lot more.”

So the pitch that was a strike in Colorado ends up in the dirt at sea level because of the added break?

“Right. But my biggest thing is, it’s not a crutch. It’s not an excuse. It’s just, it is what it is. It’s a condition that we have to work with. The same thing if you get a ball that the rub is really bad or if you’ve got a wet ball that day.

“There’s plenty of things that are thrown at us to try to gain inconsistency in this game. I don’t think we need to allow any of this to be an excuse or a crutch because we’re here long enough to where we can adapt to it. It’s significant, it is something there, but you just have to really be on top of yourself to work on it every day, understand what you need to do.”

I asked if Belisle has noticed fellow pitchers who have trouble dealing psychologically with these constant adjustments.

“I don’t know,” he said. “I know we all talk about it. I know anybody who’s new that comes over here in the past four years that I’ve been here, we talk about it and address it. But that’s up to the individual. We as teammates need to make sure we’re not using anything as an excuse, but whatever cards you’re dealt, whatever you feel that day, you’ve got to figure out and adapt how you’re going to get the guy out because you sure as heck can.

“Maybe some people can use it as a negative, but I try to look at it as an opportunity. If I can become so adept at understanding what my pitches are doing, make those adjustments here and then go on the road and feel like I’ve got even more snap with better, nasty, slow-speed pitches, and then we come here and I can adapt to that again, where a visiting team comes in and really has a tough time because they don’t play here, I feel like that’s an opportunity for me to learn myself better and really take it as a mental challenge to be tougher, because I will not allow excuses. So I look at it more as an opportunity. It’s a fight, but it’s an opportunity.”

I pointed out the dramatic deterioration in the numbers of all four potential starters — Guthrie, Moscoso, Outman and Chatwood — brought in from other organizations this year. These were adequate major league pitchers last season who suddenly can’t get anybody out, I said.

“Yeah. I don’t know what to tell you,” Belisle said. “I mean, pitching’s not easy, period. But all I can say is acknowledge that with most people there is a change in your stuff. And we all have to adapt and be on top of that. You have to do that to the best of your ability and look at it as an opportunity and do not use it as an excuse.”

You can see where the need for constant adjustments in release point would seem like a nightmare from an organizational point of view. The goal of many pitching coaches is to get their charges to find the right delivery mechanics and then repeat them over and over until they become second nature. If you’re constantly fiddling with your release point depending on where you’re pitching, that consistency of repetition is impossible to achieve.

Many fans point to opposing pitchers who come to Colorado and dominate in a single outing — say, C.J. Wilson of the Angels before the All-Star break or Cole Hamels of the Phillies on Sunday. But pitching at Coors once a year is very different from pitching there on a regular basis. Mike Hampton succeeded for half a season before crashing. Ubaldo Jimenez had a sensational first half in 2010 (15-1, 2.20), wilted in the second half (4-7, 3.80) and has not been the same since. It’s not clear if the wear is more mental or physical.

At the All-Star game, Wilson said he basically eliminated his two-seam fastball in his lone start here because he had more confidence in the lateral movement of his cutter than the downward movement of his sinker at altitude. But in a park that puts such a premium on keeping the ball down, the Rocks as an organization can hardly afford to eliminate the two-seamer from the staff repertoire.

Still, as Guthrie demonstrated Saturday night, it can take an inning to get a feel for the release point that keeps the ball down and one bad inning at Coors can be all it takes to ruin a start.

It’s also probably easier for relievers such as Belisle to make those constant adjustments since each outing is so much shorter than it is for starters. This is one of the reasons for the Rockies’ recent pitch limits on starters — to make their focus more like that of a reliever.

It’s not clear whether the failure of any Rockies starter to sustain success over a career is a function of the extra physical effort required to make balls move at altitude, the potential for injury created by constantly changing release points or the mental strain of the battle.

But Belisle’s description of his mental approach suggests that perhaps the most important attribute of a pitcher donning a Rockies uniform is mental discipline — the ability to view pitching at altitude as a challenge rather than a conspiracy to ruin his numbers. Consciously or subconsciously, the pitchers who have failed here most spectacularly seemed to blame altitude, not themselves, for their issues. Belisle, by contrast, has been a better pitcher here than he was during his previous stint in Cincinnati.

This remains the essential dilemma of big-league baseball a mile high. The effects of altitude are real; any honest pitcher will tell you that. To succeed here, a pitcher has to adjust for those effects and adjust back at sea level without resorting to the defense mechanism of blaming all those changes when things go wrong. It’s a tough psychological line to walk, and it’s tougher still to predict how any particular pitcher will deal with it before he gets here. Twenty years in, the Rocks remain a long way from a solution.