Of course, the answer to that question is a resounding NO. How unlucky could you be with the contract that Cain just signed? But, contract aside, I want to look at pitcher luck in terms of the results achieved for the quality of work produced. In other words, the relationship between wins and losses, and earned run average.

The traditional benchmark of W-L record for evaluating starting pitchers has now been largely eclipsed by ERA. Case in point is the 2010 AL Cy Young winner, Felix Hernandez, who took the trophy with a 13-12 W-L mark. Nevertheless, W-L is obviously still a prominent statistic. I can again cite Hernandez  as a case in point – there was more than a little criticism of his Cy Young selection, based chiefly on that 13-12 record. Similar reaction attended Cain’s new deal. Even a knowledgeable blogger on this site pointed out Cain’s unremarkable career .486 W-L%, rather than his career 125 ERA+, ninth among active pitchers (min. 1000 IP), and in a tight cluster on that list with such names as CC Sabathia and Justin Verlander.

After the break, I’ll take a look at whether comparison of ERA+ and W-L% can provide clues as to whether a pitcher is lucky or unlucky.

In considering luck in evaluating a starting pitcher, I started from the premise that ERA+ and W-L% should correlate strongly with each other. That is, a 100 ERA+ should correlate to a W-L% of .500, with worse ERA+ correlating with worse W-L%, and better correlating with better. Obvious stuff. That would be a perfect world where pitchers are neither lucky nor unlucky, and are rewarded with results according to the quality of their work. But, MLB is not a perfect world.

To find the most unlucky pitcher, I looked at deviations between W-L% and ERA+. That is, given a pitcher’s ERA+, which pitchers have a W-L% most significantly below what might have been expected based on that ERA+. Here’s the list, ordered by ERA+.

Gee, look who’s on top. This list is starting pitchers since 1901, with 100 decisions and 1000 IP, where career ERA+ >= W-L% x 250. Say what? This relationship is saying that, for example, a .500 pitcher would need to have an ERA+ of 125 to be considered unlucky. Similarly, a .450 pitcher would have to have ERA+ of 113, and so forth. You can argue whether this is the right search criteria, but it seems to have come up with a reasonable list. Certainly, for the top half of the list, and even for pitchers as far down as Hugh (Losing Pitcher) Mulcahy at 90 ERA+, hard to argue that their W-L% isn’t a lot worse than would be reasonable to expect based on ERA+.

Note also that only three of these pitchers pitched 2000 innings (10-12 seasons for a full-time starter today, several seasons fewer in the past). To me, this suggests that it’s hard to stay unlucky forever. And, what might this luck be? Look at the seasons represented and the teams these pitchers played for. For the most part, these guys were unlucky chiefly because they played for lousy teams. Which, to me, makes Cain stand out even more – because he hasn’t played for a lousy team. The Giants for 2005-2011 played at .494, even better than Cain’s W-L%. Similarly, Jim Scott, second on our list, played for White Sox teams that won at a .530 clip. On the other hand, Rollie Naylor’s As (.375), George Bell’s Superbas (.397) and Mulcahy’s Phils (.355) better indicate what might have given rise to their lack of good fortune.

The top 2 pitchers on our list are among only 3 with career ERA+ of 120 and a W-L% of under .500, and among only 5 with a W-L% under .550. Here’s that list.

Now for the opposite, the pitchers whose W-L% is considerably better than their ERA+ would suggest. Here’s that list.

These pitchers are those, since 1901, with careers of 100 decisions and 1000 IP, and an ERA+ < W-L% x 170. Thus, you’re considered lucky if your W-L% is .500 when your ERA+ is 85. Or, if your W-L% is .600 when your ERA+ is 102. Certainly, these pitchers, on the whole, pitched for much better teams than the guys on the first list. Just scanning the teams and years, nearly everyone played on a dominant or very good team for at least part of his career.

Jason Bere, perhaps, deserves some mention. His first two seasons, he had a 123 ERA+ and .774 W-L%, a good ERA but certainly deserving of being on this list with that improbable W-L mark. For the rest of his career, Bere did a Dr. Jekyll to Mr. Hyde transformation, compiling only a 78 ERA+ but still winning at a .448 clip (even including a 1-10 season with the 2002 Cubs). Not quite in our luckiest ever range (would have needed a .459 mark for that group), but pretty close. So, perhaps Jason is our Luckiest Pitcher ever. Lucky when he’s bad, and even luckier when he’s good.

Who do you think are the luckiest and unluckiest pitchers?