Jason Vargas Could Make Home Run History

This past Friday

*, Jason Vargas had a bit of a rough start, giving up 6 runs in just 4 innings against the White Sox. In what has been a trend for Vargas all year, most of the damage came on homers: he allowed 3 of them, scoring 5 runs. In fact, Vargas is on pace to set an MLB record for damage incurred by homer.

* That was a crazy game, by the way, with the Mariners scoring 6 runs in the 9th to take an 8-7 lead only to have the White Sox walk off with 2 runs in the bottom half.

Vargas is having a decent enough year overall; his 3.75 ERA and 100 ERA+ indicate that he’s been perfectly average. (His 4.73 FIP is subpar, however, for reasons that will shortly become obvious.) His problem has been a penchant for home runs. He’s allowed 29 of them in 27 starts so far. More than half of those homers have come with runners on base, too (13 two-run shots and 2 three-run shots), leading to a total of 46 runs scored on homers. That’s out of just 76 total runs allowed for Vargas, meaning that more than 3/5 of the runs scored against him have come on homers.

If that sounds like a lot, well, it is. In fact, if Vargas can keep up his current pace, his “Dinger Damage Rate” (or DDR; simply the percentage of runs scoring on homers) would be the highest of all time for a qualified pitcher:

I’ve included ERA and ERA+ so that you can see that most of these guys pitched reasonably well despite all the damage from balls leaving the park. Indeed, most of them are very good pitchers, and the #2 and #3 slots are held by Hall of Famers. Unsurprisingly, many of these guys pitched in relatively homer-friendly ballparks, though it is odd to see two Safeco Field-era Mariners on the list in Vargas and Jamie Moyer

.

As of right now, Vargas is on pace to become the first pitcher to allow more than 60% of his runs on homers. Unsurprisingly, Bert Blyleven

‘s legendary 1986 season currently holds the record with a 59.7% DDR. Blyleven’s 1986 also set the record for most homers allowed (50, 2 more than Jose Lima in 2000) and most runs scored on homers (80, 7 more than Moyer in 2004). And despite all that, Blyleven was still pretty good that year, thanks largely to league-leading figures in innings pitched (271.2!) and strikeout-to-walk ratio (3.71).

The next year, another future Hall of Famer nearly matched Blyleven, as Don Sutton

allowed 59.4% of his runs on homers. That year was notoriously homer-happy league-wide; the Mariners hit 161 homers that year but ranked last in the AL. For reference, AL teams averaged 162 homers in 2011, and Minnesota hit just 103. Sutton, like Blyleven, was always prone to the homer anyway. He ranks 5th all-time in homers allowed with 472 (Moyer is first with 522; Blyleven is 8th with 430).

The rest of the list isn’t quite as distinguished, though all of them had very good careers except Lew Krausse

and, to a lesser extent, Bill Travers .

If you go a bit further down the DDR list, you get some interesting diversions. One of Vargas’ fellow AL West pitchers, Ervin Santana

, is currently challenging to make the top 10–only with dramatically worse overall results. Santana has allowed 53 runs on his 31 homers. That means that 55.2% of his runs have scored on dingers, which would rank 17th-highest all-time. His ERA (5.45) and ERA+ (69), however, are terrible–easily worse, in fact, than anyone else in the top 100 in DDR. I’m guessing what sets Santana apart is not so much his crapitude as the fact that he’s somehow been allowed to stay in the rotation all year despite such crapitude (and pitching for a contender!).

On the other side of the coin, you have Pedro Martinez

‘s transcendent 2000 season, which clocks in at 30th all time with a 52.3% DDR. Pedro gave up just 44 runs that year (compared to Blyleven’s 50 home runs in 1986), of which 23 scored on 17 homers. If you didn’t hit a homer off of Pedro that year, you pretty much didn’t score. Of his 16 starts in which he didn’t allow a homer, he gave up more than 1 run just once–and that was a complete-game, 2-run effort. He gave up 7 runs total in those 16 starts, good for a 0.51 ERA. 2000 Pedro Martinez certainly had a few starts when he was off his game, but I’m not sure anyone in history has been better than he was that year when he was on his game.

Let’s also look at a related stat, the ratio of HR allowed to runs allowed. This doesn’t concern how many runners are on base, it’s simply HR / R. You can also think of this ratio as the fraction of a pitcher’s runs that were scored by the batters who hit homers. These are the 10 highest marks in history:

So in 1977, over 45% of the runs John Candelaria

allowed were scored just by the batters who hit homers. Fortunately for him, an amazing 26 of his 29 homers came with no one on base (plus 2 two-run shots and a grand slam). That’s how you can give up 29 homers and still have a 2.34 ERA.

Candelaria’s average of just 1.17 runs scored per homer is, I believe, the lowest ever for a season with that many homers allowed. John Cumberland

of the 1971 Giants had a 1.09 mark, but he “only” allowed 22 homers. Curt Schilling was similarly fortunate in 2001, as 31 of his 37 homers were solo shots. Only 9 men were on base for those 37 homers, for a 1.24 run/HR ratio.

Pedro’s 2000 season just missed the top 10, finishing 12th at .386; Vargas currently ranks 14th at .382.

As you can see from the ERA+ figures in the table, and infer from the high rankings of Pedro and Vargas, the pitchers who rated highly in this ratio ranged from about average to excellent. Of the top 50 in this stat, only Bronson Arroyo

‘s 2011 featured an ERA+ below 90; he ranked 11th with a .387 HR/R ratio but posted just a 77 ERA+. 42 of the top 50 had above-average ERAs, according to ERA+. It makes sense that most of these guys pitched well, since low overall run totals will make for a higher HR/R ratio.

Another common strand for the list above is that nearly all of the teams were excellent; only Pedro Ramos

‘ 1963 Indians finished below .500 (and that just barely), while two of the teams (the ’01 Diamondbacks and ’02 Angels) won the World Series. Perhaps these teams were great defensively, which helped keep runners off the basepaths? Or maybe the pitchers and their teams were just lucky? Or maybe they had great pitching coaches or something else going on that’s not obviously reflected in the numbers? It’s an interesting correlation to ponder.