Johan Santana: Mets ace may never be the same

There is quite literally a hidden beauty in baseball, one nobody has seen live or ever will because it takes place beneath the skin. The shoulder is a fascinating beast, untamed, undefeated. Players receive injections with stem cells made of their own fat and steal a tendon from their wrist to fix their elbow and still, no one has solved the shoulder, at least not with any level of certainty. It is baseball's Moby Dick.

Doctors, trainers, GMs, managers and especially pitchers want to better understand what happens when ball escapes hand at 95 mph or when a curveball snaps off the fingertips – how the kinetic chain unfurls and how the four muscles which comprise the rotator cuff and the oddly named bones (coracoid process, acromion, glenoid) and the rest of the ligaments and tendons rotate and flex and retract and abduct. As much as biomechanics can explain the process, it has not answered the questions which would forever change the game.

What makes the shoulder break?

How can we fix it with great degrees of success?

Nobody musters more than a shrug. Body parts tear, rip, shred. Throwing a baseball 100 times a game every five days is to the shoulder what offensive linemen bashing their helmets every play is to the head. It is not meant to withstand that, and baseball built its sport upon it anyway. Tommy John surgery conquered a torn elbow ligament. The shoulder could use such a benefactor.

At the moment, Johan Santana looks like little more than another iffy candidate. Tuesday in Port St. Lucie, Fla., he threw 29 pitches over two shutout innings against the St. Louis Cardinals in his first action against major-league hitters since Sept. 2, 2010. Less than two weeks after that start, Santana underwent surgery on his left shoulder for an anterior capsule tear. He tried returning in August 2011. After five Class A innings, his shoulder barked no.

That the New York Mets still have him penciled in for an opening-day start this season is either a reflexive response to the painful salaries they owe him for the next two years – $54.5 million, assuming they turn down a 2014 club option – or extreme faith in something with little history to warrant it. The list of pitchers who returned from capsule-tear surgery to anything near their previous level reads like this:

It killed Mark Prior's career, slowed down Chien-Ming Wang's, halted Pedro Feliciano's and derailed dozens more before doctors could identify the exact problem. It's why when pitchers go in for MRIs, they beg for the doctor to say: "Elbow."

"We know the shoulder; we just don't know how to get it like the elbow," said Sandy Alderson, the Mets GM who inherited the back half of Santana's six-year, $137.5 million deal. "Shoulder surgery is much more problematic. And because we don't have as much as a history, it's hard to predict where he'll go and how long it'll take him to get there."

It's easy to forget how good Santana was before his injury. He won two Cy Young Awards with Minnesota. His career adjusted ERA, which measures him against all starters in history while weighing era and park factors, is tied for seventh best with another shoulder casualty, Brandon Webb. When the Mets traded for Santana and signed him to the extension, it seemed like a potentially bad deal only because of the danger in signing pitchers that long – not because Santana had shown any particular predilection toward injury. On the contrary, he delivered his pitches free of hitches and kinks.

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When Santana's velocity started to wane, the worries about his long-term health contrasted with his numbers. If he was so hurt, how could he throw up a sub-3.00 ERA, as he did in 2010? It's a testament to Santana's brilliance as a pitcher, something that ought to serve him well as he reinvents himself.

"I'm just trying to do everything the way I used to do it," Santana said earlier this spring, and while that's nice to think, it's not realistic. He'll never sit at 93 mph again. The Mets are targeting him for 25 starts and well below the 229-inning average he set in his five-year prime which compares favorably with any in the post Maddux-Pedro-Johnson era. For now, with the Mets the only team in the National League East without a chance to compete for a playoff spot, Santana's biggest goal may be to salvage his contract.

Before the injury, it wasn't exactly wretched. According to Baseball-Reference.com, Santana logged 14.4 Wins Above Replacement in his first three seasons with the Mets. If a marginal win is worth around $5 million in free agency, his performance more than covered the $60 million New York paid him for those first three years.

Problem is, the fourth was worthless. The fifth and sixth remain enormous burdens. And Santana could become another bust on the list of $100 million pitchers. For his $111 million, Mike Hampton delivered 5.3 WAR thanks to a wrecked shoulder. Barry Zito doesn't have that excuse for his 3.8 WAR for $126 million – or $33,157,894.70 per win. Daisuke Matsuzaka is out till the summer after his elbow blew up. Kevin Brown was hurt four of his seven seasons and was the best of that bunch.

The likeliest success stories actually are the most recent. Perhaps that's because neither is close to the end, by which time the pitcher often has broken down. After three successful seasons with the New York Yankees, CC Sabathia opted out of his $161 million deal and got a new-and-improved $122 million contract. Year 1 of Cliff Lee's $120 million gamble netted him nearly 7 WAR. And the newest entrant into the club, Yu Darvish, starts a six-year deal for which the Texas Rangers paid $111.7 million.

It's an odd mix, the teams which have handed nine figures to pitchers: the numbers-wary Giants and Mets and the stat-savvy Boston Red Sox, Yankees and Rangers. The willingness to bet so much on something so unknown seems irresponsible, bordering on unthinkable.

"You've got to take those actuarial facts into account," Alderson said. "It doesn't mean you don't do it. It doesn't mean there aren't exceptions. But looking at it from strictly a risk and probability standpoint, you have to be careful.

"I didn't say the actuarial tables ruled decision making; you have to proceed at your own risk."

Translation: Alderson would still give $100 million to a pitcher – probably someone just like Johan Santana when he signed with the Mets.

And even though "everybody's optimistic," Alderson said, that's their only choice because there's no sense in ruing dumb luck or sunk costs or praying the Shoulder Fairy does to Santana what it refused to so many others. The Mets need it and Lord knows Santana does, too, to keep him from regretting the potential Hall of Fame career gone wrong, from spending all his time pursuing a countersuit against the woman who claims he sexually assaulted her at a Fort Myers, Fla., country club.

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"I've been waiting for this too long," Santana said, and now it's here – or at least the next part. Since camp broke, he has progressed from throwing off the mound to amping up his pitch count to face hitters in batting practice to this: two innings and 35 pitches, a test lap for his shoulder. Just finish without crashing. Just finish.

It's so much to ask, too much probably, for the man with the torn-up shoulder to throw a baseball at ungodly speeds with impossible precision through an incessant workload. The entire racket illuminates a truth that uglies up the beauty of the shoulder's pieces and parts working in concert: For all of the excitement a single pitch can generate, it also contributes wear on an arm that one day will just give up, another white whale that got away.

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