When CC Sabathia was in his prime, dominance seemed to follow regardless how sharp his stuff was in a particular outing. Upon arriving to the New York Yankees in 2009, the perfect blend of talent and maturity accompanied the big lefty to the Bronx. 

With a 94-96 mph fastball and the wisdom of eight years of big league pitching under his belt, Sabathia dominated AL East rivals and helped the Yankees win a World Series. Like any pitcher, decline was expected to eventually arrive, but smarts and pitching acumen were poised to get Sabathia through the years when his fastball and sharp stuff no longer appeared.

Or so we thought.

On Friday night, Sabathia was cruising against the Boston Red Sox in an early-season clash of titans in baseball’s toughest division. Through five innings, Sabathia’s performance rivaled his best days as Boston couldn’t buy a run. 

Then, in a the span of an inning, it all fell apart. When Sabathia’s sixth-inning slider to Grady Sizemore missed its target, a game-winning home run ensued. With the blast, questions once again emerged around a pitcher that the Yankees owe $76 million through the end of the 2017 season. 

At this point, it’s a fool’s errand to expect Sabathia’s fastball to return to the speed it once routinely touched. From 2004-2011, Sabathia’s average fastball velocity never dipped below 92.9 mph in any season and topped 94 mph in two separate years. 

It was that velocity—coupled with great secondary stuff, command and control—that made Sabathia one of the best pitchers in baseball. From 2002-2011, spanning Sabathia’s age-21-30 seasons, he won 159 games, pitched 2,184 innings, posted a 3.44 ERA, ERA+ of 127 and was worth 47.7 WAR. 

To put those numbers into perspective, consider this: Over that 10-year span, only two pitchers—Roy Halladay and Johan Santana—were more valuable. Only two—Halladay and Mark Buehrle—pitched more innings. Only one—Javier Vazquez—struck out more batters. Among pitchers with at least 1,500 innings pitched during that time frame, only three—Halladay, Santana and Roy Oswalt—owned a better adjusted ERA.

Sabathia was dominant, partly because of his ability to keep the ball in the ballpark. As his career has hit the skids, it’s that—more than just velocity or diminishing stuff—that has made him so vulnerable to the big inning and game-changing hit. 

FanGraph’s HR/FB rate has been tracking fly ball data since 2002, Sabathia’s second year in the league and the start of his dominance. On a yearly basis (with the exception of 2005), less than 10 percent of fly balls hit against Sabathia flew over the wall for home runs. 

Over the last three seasons, including a very small-sample size of three starts in 2014, that number has exploded to 12.5, 13.0 and 38.5 percent, respectively. The decline of Sabathia’s stuff has been the trigger for issues, but the damage done when the ball is hit in the air is causing everything else to become magnified in New York.

Regardless of the innings Sabathia piled up in his prime, opposing hitters rarely tagged him for an inordinate amount of home runs. From 2002-2011, Sabathia surrendered an average of 19 home runs per season. 

Since Opening Day of 2012, he’s allowed 55, including Sizemore’s blast on Friday night against the Red Sox. 

It’s likely that the Yankees have come to terms with the southpaw’s struggles, downturn in velocity and diminishing returns, but the home run rates and bad innings are becoming alarming. Despite feeling good about this pitcher for five or six innings per start, a home run usually arrives to unravel all of the solid work done. 

The remainder of the 2014 season can’t be about velocity or innings or toughness when it comes to evaluating Sabathia’s chances at resuming his role as a top-of-the-rotation pitcher. Instead, it has to be about his ability to keep the ball in the ballpark. 

If he can limit home runs, results will follow. If he can’t, the Yankees are going to spend a frustrating summer explaining why Sabathia looks, feels and pitches fairly well, yet games end in heart-breaking fashion in the Bronx.

Agree? Disagree?

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Statistics are from Baseball-Reference.com and FanGraphs unless otherwise noted. All contract figures courtesy of Cot’s Baseball Contracts. Roster breakdowns via MLB Depth Charts

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