Eye-popping numbers illustrate how Red Sox have struggled to do little things all season

If it seems like the Red Sox aren't doing as many of the little things this season, the numbers bear that out.

From baserunning to defense to situational hitting, the Red Sox have largely taken a step back in 2019, and the differences -- even if they often appear slight -- have led to a big swing in the standings.

On this date a year ago, the Red Sox were 90-42, six games up on the Yankees in the AL East. Today they're 70-62, 15 games behind the Yankees and six out of the wild card.

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While the obvious culprits for their decline can be found in the starting rotation, where the Red Sox are just 19-27 in games started by aces Chris Sale and David Price, they've scuffled on the margins in impactful ways, too.

Let's start with offense. The Red Sox rank third in the AL in runs with 757, but they haven't distributed them very evenly. They're 16-1 when scoring at least 10 runs. Last year they not only went 20-0 when scoring at least 10 runs, they were unbeaten the 37 times they scored at least eight.

This year they've lost five such games, but where they've really struggled are the low-scoring contests that can spell the difference between 85 and 95 wins. Last year they went 38-21 when scoring between three and five runs for a .644 winning percentage. Compare that to now, when they're just 15-30 in those games, which is good for a winning percentage of .333. That's nearly twice as bad as a year ago!

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Certainly a bullpen that has blown 24 saves in 49 chances deserves some blame. But let's not exclude the offense. Winning a 3-2 game can come down to advancing a runner, and the Red Sox have struggled in this arena all season.

Last year they ranked sixth in productive outs, advancing runners 29 percent of the time. This year they're 23rd at 25.2 percent. A year ago, they drove in 50.8 percent of runners from third with less than two outs, good for eighth in MLB. This year, they're at 47.5 percent, which ranks 24th. Last year they advanced a runner from second with no outs 55.2 percent of the time, which ranked sixth. Now they're at 48.5 percent, which is 24th.

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That's a lot of missed opportunities, and we've seen it in their approach all season, whether it's Christian Vazquez popping up with runners in scoring position or Mookie Betts skying to right-center instead of pulling the ball to left, where he does most of his damage. Maybe it has cost the Red Sox 20 runs total, which equates to about two wins. Those two wins alone would vault them over Oakland in the wild card race and close the gap on Tampa.

Baserunning hasn't helped. A year ago, the Red Sox led baseball by converting 80 percent of their stolen base attempts. This year they're at 70 percent, which ranks 20th. In one minor surprise, they've only run into 37 outs on the bases (9th fewest), which is better than last year's 57 (22nd).

Then there's defense. Because public defensive metrics remain unreliable and often contradictory -- by total zone rating, Jackie Bradley has cost the Red Sox runs, but by defensive runs saved he's a net positive -- it's best to just stick with some general numbers.

Defensive efficiency simply states the percentage of balls in play that become outs. Last year, the Red Sox ranked 12th in baseball at .693. This year they've fallen to 26th at .675.

That's a lot of numbers, and they can get a little confusing, but here's the upshot -- the Red Sox aren't just struggling because their big stars have collectively regressed. There are a whole bunch of little areas where they're coming up short, too.

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