There is no use in attempting to accurately predict a pitcher's future value, the unenviable task that currently consumes Ruben Amaro Jr. and his lieutenants. They could look no further for evidence Friday than the mound at Citizens Bank Park, where two-time Cy Young Award winner Tim Lincecum lugged a 5.93 ERA into his 20th start of the season.

Although he got the win Friday night, he has been stumbling through the first year of a two-year, $40.5 million deal, a pact greeted with disappointment January in San Francisco because it was not long enough.

Now? Everyone has a theory about why the long-haired pitcher has soured. Giants manager Bruce Bochy has had to deflect questions over a brewing controversy about Lincecum not wanting Buster Posey, the franchise's star, to catch him. Some say the diminutive righty's mechanics are flawed. Others see weakened velocity and wonder about an injury.

These things happen. Throwing a baseball thousands of times is an unnatural act prone to outcomes that can be unforgiving and unpredictable. It is why Cole Hamels' progression from pimple-faced draft pick to World Series MVP to frontline pitcher is so fulfilling for the Phillies and their fans. It is why he is worthy of a long-term contract extension, one that could be the largest contract ever signed by an athlete in Philadelphia sports history.

Hamels will pitch Saturday in what could be his final home start as a Phillie, although the chances of that are diminishing. This outing will be undersold by those involved, hyped on national television, and not unnoticed by those in attendance. It should be less a celebration of his career and instead a final rally toward a sensible union.

Make no mistake: The Phillies will be taking their greatest risk if they sign Hamels to a six-year deal, simply because of the length. It's a risk, of course, they must take. There is no indication they have formally offered six years to Hamels' camp, but the negotiations are reportedly trending in that direction. That should come as no surprise. The Phillies set Hamels' value when they signed a 32-year-old Cliff Lee to a five-year, $120 million deal in late 2010.

Until then, the Phillies had adhered to a policy of not signing pitchers to contracts greater than three years. It was a tenet of Pat Gillick, who remains an integral part of the front office even as Amaro stretches the limits.

Relaxing the rules for Lee immediately followed a six-game defeat in the National League Championship Series to the Giants, and one cannot help but wonder how much those nine days affected Amaro's philosophy. The Phillies scored 20 runs in that series and allowed 19. That begot the Four Aces.

Gillick's policy was prudent in a different market. Baseball is littered with examples of failed long-term deals of six or more years for pitchers - Barry Zito, Mike Hampton, and Kevin Brown come to mind. But Gillick has always maintained there are exceptions to the rule. Hamels fits the bill.

He is 28, throws four pitches with conviction, and has required a trip to the disabled list only three times in his career. He has risked millions of dollars each time he has thrown in 2012, but has remained cool, confident, and even a little cocky. His agent, John Boggs, probably sweats a tad more.

Hamels could have taken the route of his Saturday counterpart, Matt Cain. It's fitting Hamels makes this start against Cain, whose six-year, $127.5 million deal signed on opening day had a direct effect on his asking price. Cain is the game's richest righthanded pitcher. Hamels could wait until free agency and possibly top CC Sabathia for the most lucrative pitching deal ever, but a sixth year from the Phillies could dissuade him from doing that.

If he signs, the Phillies staff suddenly resembles that of the Giants in financial terms. (San Francisco has found a way to make the rest of the roster competitive, too.) Hamels and Cain could have nearly identical deals. Lee and Zito are similar in money, not years. The remaining time on Roy Halladay's deal mirrors Lincecum's. Vance Worley has ground to cover before he catches Madison Bumgarner, who recently signed a club-favorable, six-year deal.

If $24 million is Hamels' annual figure, the Phillies would be committing $68 million to three pitchers in 2013 and approximately $137 million to 10 players for 2013. (That is using average annual value of contracts and also assuming the Phillies exercise a $5 million team option on Carlos Ruiz.)

There are luxury tax implications, and the immediate by-product of a Hamels deal could be the selling off of Shane Victorino, Joe Blanton, and Placido Polanco to avoid being taxed in 2012 so there are fewer restrictions on spending for 2013.

Savor the image of Hamels in red pinstripes Saturday, just in case. There are no guarantees afterward, no matter which team signs Hamels. Six years is a long time, but the first fruitful decade of this relationship demands such a risk.

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