It's easy to look at the raw numbers of past pitching staffs under Bob McClure, who the Phillies hired as pitching coach Monday, and point and laugh and gasp for what may be yet to come here in 2014.

But it's not that simple -- something we learned during the time of the guy McClure replaced in Philadelphia.

Sure, coaching can have a tremendous impact on an organization's arms. Just take Red Sox skipper John Farrell, who arrived this season in Boston with a renowned pitching pedigree and helped make one of the worst staffs in baseball into one of its best, en route to a legendary whole-team turnaround and World Series win. Farrell was vital for the Red Sox.

But there's only so much proverbial chicken salad a coach can make, given the quality of the, um, available chicken. And during McClure's time in Kansas City (2006-11) and Boston (2012), that "other" chicken was in ample supply.

Consider McClure's cupboard during his first big league stint: Mark Redman. Scott Elarton. Odalis Perez. Brian Bannister. Kyle Davies. David Riske. Yeah. Yuck. So should it surprise that McClure's Royals staffs finished with, in order, ERAs of 5.65, 4.48, 4.48, 4.83, 4.97, and 4.44, ranked, in order, worst, 16th, 22nd, 26th, 29th, and 27th?

Ultimately, when it comes to sizing up the impact of any coach on any level, there are two major considerations to be had: How did players do before him? And how did they do after/without him?

With McClure in Kansas City, it was simply more good than bad.

A few guys did just fine under him.

One was a former Baseball America No. 14 prospect who threw well in 2004, his rookie year, but stumbled mightily the following season, posting a 5-17 record and 5.80 ERA. He would go on to miss 69 games during the 2006 season with a rare case of social anxiety disorder, but by the time he left McClure in 2011 for Milwaukee, and, later, both clubs in Los Angeles, he would revitalize his career, sticking a 2.91 ERA between 2007 and 2009, the third best among starters over the span, and taking home the 2009 American League Cy Young award.

Who was he? Zack Greinke.

Another erupted on the scene in 2007 and never looked back, posting a 2.01 ERA in 238 games through 2010 that ranked third among AL relievers -- one slot ahead of Mariano Rivera -- and grabbing two All-Star bids.

You remember Joakim Soria, don't you?

Of course, two former top 100 prospects that came up during McClure's tenure in Kansas City, Luke Hochevar and Daniel Cortes, never panned out. But that wouldn't make for the first time that a pair of top prospects didn't stick. And just like the successes of Greinke and Soria were more a function of the player than the coach, so too, it stands to reason, could have been the failures of Hochevar and Cortes.

Things we should have probably learned during former Phillies pitching coach Rich Dubee's 13 years here. When Roy Halladay, Cliff Lee and Cole Hamels pitched at Cy Young caliber, was Dubee the X-Factor? When Halladay's arm gave out, Hamels tried to do too much and Chad Durbin, Raul Valdes, Jeremy Horst and Mike Adams happened, was Dubee solely to blame? Of course not. Should he have ever been fired? Maybe not.

Unfortunately, failure often leaves few survivors. That seemed to be the case in 2012, when the Red Sox began tumbling toward their worst record in 40 years and fired McClure in August. Their ERA that month? 5.54. And in September? 5.11. They improved in 2013, but not without an entire house cleaning in their bullpen, the return of John Lackey from a Tommy John surgery and the riddance of Josh Beckett from their rotation and clubhouse. Not to mention the going of the toxic Bobby Valentine with the arrival of the inspiring Farrell.

For the Phillies, there's much at stake here with McClure.

Cuban defector Miguel Alfredo Gonzalez needs to fill a rotation spot. Up and coming relievers Jake Diekman, Justin De Fratus and Joe Savery excelled last year, and need to be developed further. Ethan Martin probably needs to transition from middling starter to middle reliever. Top prospect Jesse Biddle may at some point get the call, and needs to capitalize on his talents once here. McClure stands to have a major impact in all cases.

But while there are few assurances that McClure will play savior -- especially considering he was at least the Phillies fourth preference, considering they first offered the job to Roger McDowell, Jim Benedict and Jeff Pico, according to Matt Gelb of the Philadelphia Inquirer -- there's nothing about his resume that suggests he's likely to ruin anybody or anything. Especially given much of the mess that's awaiting him.

Matt Hammond covers the Phillies for 97.3 ESPN-FM. 

Follow him on Twitter at @MKH973. Catch him every Saturday from 12-2 on “Sports Bash Saturday.”

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