Red Sox closer Aroldis Chapman is doing 2 incredible things he's never done in his MLB career

From the moment Aroldis Chapman stepped foot in the United States and started to throw a baseball, he amazed everyone who watched him.

But even one of the most gifted left arms in the history of baseball has never been quite this good before.

Chapman is 37 years old and wasn't even a sure thing to be the closer for the Red Sox before this season started.

But now, he's having the best statistical season of his career in two major categories.

The first is ERA, where Chapman currently sits at 1.50. He's never finished a season that low in that statistic before.

The other is walk rate. Chapman is putting on 2.8 batters per nine innings, the lowest mark of his career.

That's frankly remarkable.

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Chapman has always been special, but the fact that he potentially is still improving is extra amazing. Maybe he changed his mindset. Maybe he changed his mechanics. Whatever the explanation, the results are astounding.

Being a relief pitcher is a funny business statistically, because those numbers could change in a hurry with one or two bad outings.

But in reality, Chapman has shown he's still got it, and Boston is a huge beneficiary so far.

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