A familiar axiom in baseball is there’s no such thing as a pitching prospect.

The idea behind it is that even the best or most talented young pitchers can have their promising careers derailed in a twinge of an elbow or a tweak in mechanics.

Sometimes they overcome the obstacles; other times they don’t. But the constant battle pitchers face of trying to stay healthy while at the same time pushing their bodies to the limit is what makes it so difficult to succeed in the majors.

Yet every year, a few young pitchers do manage to put everything together.

Here are five pitchers who have the talent and the opportunity to be this year’s breakout candidates. All five are former first-round picks who have had their share of adversity, but are trending upward as the 2017 season begins.

Dylan Bundy, Baltimore Orioles

The fourth overall pick in the 2011 draft, Bundy made his major league debut the following year at age 19. But Tommy John surgery cost him all of 2013 and shoulder problems kept him from pitching above Class AA ball until last season – when he threw a career-high 109 2/3 innings, spending the first half in the bullpen and making 14 starts after the All-Star break.

Now 24, the worry of reinjury isn’t weighing him down anymore. “It did last year. Every now and then, it popped in my head but come August and September I was forgetting about my arm or my shoulder and elbow,” Bundy says. “That gave me more confidence out there on the mound.”

Armed with a mid-90s fastball, plus an above-average curveball and changeup, Bundy’s newfound confidence has him working this spring on adding a hybrid cutter/slider to the mix.

Or re-adding. That pitch was one of his best weapons when he had scouts flocking to Owosso (Okla.) High School to see him, but he stopped throwing it after his elbow surgery.

“I didn’t want to throw that cutter/slider thing last year. I wanted to get a full year healthy in the big leagues and get my arm strength built back up,” he says. “If I can just add one more just to give ‘em a different look, I think it will help.”

In his first two appearances this spring, Bundy allowed one earned run in five innings with five strikeouts and no walks. Even more, he’s getting more comfortable throwing the cutter again – and not just as a chase pitch with two strikes.

Taijuan Walker, Arizona Diamondbacks

Bundy isn’t the only young pitcher looking to expand his repertoire this spring.

After being traded by the Seattle Mariners to Arizona in the offseason, Walker began working on a slider to give him an advantage in the ever-changing battle of adjustments vs. hitters. In particular, he watched video of Tampa Bay Rays pitcher Chris Archer, who has one of the game’s best sliders and who has an arm slot similar to Walker’s.

“I’ve been working on it a couple years, but it hasn’t been there. It’s been more of a cutter. But I feel like so far in spring, it’s been more of a slider,” he says.

“It’s the biggest pitch I wanted to work on just so I had something to throw against righties so it’s not just fastball, changeup to righties. I could mix in a slider for a swing and miss or weak contact.”

The results so far have been excellent. Walker, 24, pitched nine scoreless innings over his first three spring starts, with 13 strikeouts and only one walk. He’s also drawn rave reviews from new manager Torey Lovullo.

“He seems to have incredible mound presence. He’s on the attack. He has a lot of those great qualities that you look for in a starting pitcher,” Lovullo says. “I don’t want to shoot too high, but he’s a pretty special guy.”

Walker was plagued by bone chips in his ankle last season that eventually required surgery. The 2010 first-rounder (43rd overall) finished with an 8-11 record and 4.22 ERA for Seattle. A move from the American League to the National League is usually good for a pitcher’s stats. Good health and a new slider should raise his stock even higher.

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James Paxton, Seattle Mariners

Coming up through the Mariners system together, Paxton and Walker both reached the majors in 2013. They were frequently mentioned in the same breath as the team’s top pitching prospects. And they planned to work out together in the offseason until Walker was traded.

In parts of four major league seasons, Paxton lacked consistency. And in every one of those seasons, the left-hander also spent some time at Class AAA Tacoma.

The most disappointing one was last year, when a poor spring training resulted in him starting the season in the minors. That turned out to be a godsend when he was reunited with pitching coach Lance Painter, who helped him tweak his delivery.

“I was getting a little too high with the arm slot so I got down to a bit more comfortable position,” Paxton says. “It was almost instant that the ball was coming out of my hand better and I was throwing harder and I was feeling really good again.”

The mechanical changes resulted in a more consistent delivery. All of a sudden – at age 27 — he was throwing his fastball harder than ever, hitting the mid- to upper 90s. And with better control.

When he returned to the majors in June, the results didn’t necessarily follow. In 20 starts, Paxton finished with a decent 3.79 ERA but allowed 134 hits in 121 innings, resulting in a subpar 1.31 WHIP. However, his 96.7 mph average velocity ranked third in the majors among starters, trailing only Noah Syndergaard and Nathan Eovaldi.

“There were games last year where I felt like I had pitched better than the results showed,” Paxton admits. “You have to keep on going.”

Digging a little deeper, he was pitching much better. Paxton’s Fielding Independent Pitching, which is based on only the factors pitchers can control, was nearly a full run lower than his ERA at 2.80.

That figure would have been the best in the American League if he pitched enough innings to qualify. (Corey Kluber led at 3.26.)

In two appearances this spring, he’s allowed a pair of homers in five innings. But he’s struck out seven batters and walked one.

“Maybe I had some rotten luck last year but I just continue to focus on my process and give myself a chance to be successful.”

Daniel Norris, Detroit Tigers

Another hard-throwing lefty, Norris has been plagued by a number of health issues throughout his career, including thyroid cancer two years ago.

Now cancer-free (“I had my one year checkup in December. Everything was clean still. I thank the Lord for that.”) he can focus on building on the progress he made splitting last season almost evenly between Class AAA and the majors.

Norris, 23, had a solid 3.38 ERA, but a 1.40 WHIP in just under 70 innings with the Tigers, striking out more than a batter per inning.

The most valuable piece of advice has come from pitching coach Rich Dubee, who told him he didn’t need to improve any of his pitches.

“Your stuff is that good. But you have to be able to eliminate the noncompetitive pitches,” Norris recalls, which reminds him not to try too hard to strike batters out. “When I get in trouble is when I throw so many pitches in a game because I’m throwing 0-2 fastballs eye-high.

“And nobody is going to swing at that.”

This spring he’s struggled some with his control but has been able to work his way out of trouble (2.16 ERA in 8 1/3 innings). One area he knows he needs to improve is against right-handed batters, who hit .290/.332/.469 against him in 2016 with an OPS more than 150 points higher than he allowed against lefties.

For Norris, it’s just a matter of being able to throw his secondary pitches – his slider, curve and changeup – for strikes.

“I have confidence in myself,” he says. “Once I finally had a healthy stint in the big leagues, I showed what I could do.”

Mike Foltynewicz, Atlanta Braves

The offseason acquisitions of veteran pitchers Bartolo Colon, Jaime Garcia and R.A. Dickey, plus the return of ace Julio Teheran doesn’t leave much room in the starting rotation for youngsters Foltynewicz, Matt Wisler and Aaron Blair, who made a combined 63 starts for the Braves last season.

Of the three, Foltynewicz has the most powerful arm, averaging over 95 mph on his fastball. On a team that finished 68-93, he was the only pitcher to make more than three starts and have a winning record, going 9-5 with a 4.31 ERA over a career-high 123 1/3 innings.

With three solid outings to start the spring (2.00 ERA, 1.00 WHIP in 9 innings), Foltynewicz, 25, is the front-runner to claim the final spot in the rotation.

“It’s just about him learning to command his fastball,” says manager Brian Snitker. “Once those guys who have the stuff like he does commands their fastball, they become a really good pitcher.”

There are already signs he’s getting there. Like Walker, Foltynewicz does a good job of getting ahead of hitters with a 63.4% first-strike percentage. (Among the 118 pitchers with at least 120 innings, both were in the top 35.) Even more encouraging is his above average swinging-strike rate (10%) and the improvement he made last season cutting down his walks (2.55 BB/9).

“He’s a young pitcher learning,” Snitker says. “Upside is really really big, too.”

The Braves manager was speaking about his own pitcher, but the same could apply to the other four as well.

Gardner reported from Arizona and Florida

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