How MLB’s home run spike has affected Pittsburgh Pirates pitching

On Tuesday, Alex Gordon hit the 5,694th home run of this season by all combined MLB hitters. The long ball broke the single-season league record set in 2003 and the statistic continues to grow in home-run-happy 2017. Here’s how Pittsburgh Pirates pitchers have fared in this launching pad of a season.

Hitting home runs has never been the Pittsburgh Pirates’ forte. At least not in the last 10 years. Only once since 2008 have the Pirates ranked in MLB’s top 10 in home runs hit.

This season, Pittsburgh is second to last in MLB with 144 home runs. In a year that MLB has set its single-season record for most home runs by all of its players combined, the Pirates have not been a huge help.

Consider the following statistic…

Now, consider that the Pirates only have two players that fit that criterion: Andrew McCutchen (26) and Josh Bell (24).

Meanwhile, several other teams are setting franchise records with how stacked their lineups are with power hitters.

Despite their struggles with hitting home runs, the Pittsburgh Pirates have been impressive at not giving up many home runs in this anomaly of a season. That said, Pirates pitchers’ success at surrendering minimal home runs is not an anomaly this year.

Looking back

Simply put, the Pittsburgh Pirates have been among the leagues’ best at allowing the fewest home runs despite such a poor record. For 2017, Pittsburgh’s 174 home runs allowed is fifth-fewest in MLB.

Below is a list of home runs hit and allowed by the Pirates in the last 10 seasons with their rankings among MLB teams in parentheses.

Pirates Hurdle-Era HR Snapshot

YearHR hitHR allowed
2017155 (29th)174 (25th)
2016153 (26)180 (20th)
2015140 (23rd)110 (30th)
2014156 (6th)128 (22nd)
2013151 (14th)101 (30th)
2012170 (12th)153 (20th)
2011107 (27th)152 (15th)

Aside from a few dreadful seasons, the Pirates have consistently been among the best in MLB in fewest home runs allowed despite a struggle to hit many.

To help quantify whether the cumulative number of home runs allowed per year is above average, let’s look at the Pirates home runs allowed per nine innings each year in the last 10 years.

As the Pirates made an effort to focus on ground balls within the last five years, fewer balls left the ballpark from 2013-15 when they made the playoffs each year. In the last two years, it’s risen to 1.12 and 1.15, respectively. The 1.15 home runs allowed per game in 2017 are the Pirates highest in the last 10 years. That said, in 2008 when they allowed 1.09 per game, it was seventh-highest in MLB. The 2017 rate is 26th.

The most important reason for why the Pirates hit so few home runs and give up so few may be because of the field that they call home.

PNC Park effect

PNC Park has long been regarded as a pitcher’s park. Statistics certainly back that up. This season, batters at PNC Park are averaging 1.88 home runs per game, 0.05 better than last season, according to ESPN Home Run Tracker. In fact, batters haven’t averaged at least 2.00 home runs per game at PNC Park since ESPN began tracking home runs in 2006.

Home runs are up at PNC Park this year despite the Pirates being in the cellar for home runs hit and at the top of fewest home runs allowed. Credit this to the home run spike across MLB.

While the Pirates may be among the worst in baseball at hitting home runs, they’ve nonetheless hit more home runs this year than they have in four of their previous nine seasons. That includes 2015, when the 98-win Pirates slugged 140 home runs.

From the pitching aspect, the Pirates have given up more home runs in 2017 than in all-but-two of their past 10 seasons. Yet, they are the fifth-best team at home run prevention.

Credit PNC Park as the primary antagonist to home runs hit by Pirates hitters at home, but also count it as the main protagonist for pitcher home run prevention.

PNC Park’s dimensions are extremely beneficial to allowing fewer home runs. Consider the difference between it and hitter-friendly Miller Park.

Batters at Miller Park average 2.21 home runs per game, 12th-best in MLB. Meanwhile, hitters at PNC Park average 1.65 home runs per game, second-worst in MLB. Something as simple as smaller dimensions in left-center field can make a huge difference in home runs allowed.

However, also credit the spike and the inflated statistics for them seemingly moving up in the number of home runs allowed yet very little change in overall league rankings. As more and more “three-outcome hitters” emerge, home runs have shot up. Speaking of three-outcome hitters…

Home runs up, strikeouts up

As players swing for the fences, they’re missing the ball far more often than hitting it. New York Yankees’ outfielder Aaron Judge leads A.L. rookies and is second in MLB with 45 home runs, but his 31.2 strikeout percentage is tops among rookies and sixth-worst among qualified MLB hitters.

MLB pitchers are wracking up the strikeouts in addition to home runs. Pirates pitchers have struck out 1,192 batters, 19th best in MLB. So, the Pirates are among the best in MLB in fewest home runs allowed and are slightly below the league average in strikeouts. Meanwhile, MLB’s leader in strikeouts by pitchers (1,500), the Cleveland Indians, have allowed the fewest home runs (155).

Strikeouts across the league are up as a whole. The Pirates only need to average just over 4.4 strikeouts per game over their final nine games to match last season’s total.

Here’s a look at the Pirates strikeouts per nine innings per year for the last 10 years.

It’s clear that even as Pirates pitchers have given up more home runs, they’ve also struck out more batters. Just as the number of home runs given up this season is not too different from their team rankings a few years ago, the 2017 Pirates pitching staff’s K/9 isn’t that different from a few years ago. In 2017, their 7.88 K/9 is 19th best in MLB, but their 7.59 K/9 in 2014 was 18th best. Strikeouts are up, but rankings are not changing.

Inflated statistics

The biggest thing to note from this season’s numbers is that the numbers are inflated, but the Pirates rankings across MLB are not too different from recent years. Since the Pirates have not qualified for the playoffs in the last two seasons, there is an obvious regression, but it’s not as if they are much worse than the rest of the league in terms of home runs allowed and opposing batters struck out.

Nonetheless, though the cumulative numbers look larger than usual, the Pittsburgh Pirates pitching has not been that much worse than previous years in terms of home runs allowed and strikeouts.

The home run spike is to blame.

Image credit – Daniel Decker Photography

Joel Norman

Joel Norman is a journalism major at West Virginia University. In addition to writing for Pirates Breakdown, Joel covers WVU sports for the Daily Athenaeum and writes game recaps and features for the Pittsburgh Riverhounds. Joel also does play-by-play broadcasts of WVU hockey and baseball for WWVU-FM in Morgantown.