May Days, May Daze, Maydays...

I don't think anyone will be sorry to see the back of May here, as the team slumped from a 19-8 record in April, down to a sorry 11-17 in May, a dropoff of 8.5 games. Bad though that was, we've had worse collapses, and fairly recently. In June 2006, we slumped 10.5 games, going from 18-9 in May, to 8-20 the following month - the good news is, we came right back to 16-9 in July. [The problem that year was largely one of consistency - we never had two winning months - or two losing ones - back-to-back the entire season] Let's drill down from that raw 11-17 figure, and see what we can find for causes.

Let's start with run differential. In May, we scored 161 runs and conceded 107 - outscoring our opponents by an average of two runs per game. Using Pythagoras, this projects to a record of 19-8, which is exactly what we achieved. We really were that good in April, folks: we weren't "lucky". In May, as I'm sure you would expect, the story was radically different. We scored only 117 runs, almost two less per game, and conceded 125. While it probably didn't seem like it, we weren't actually outscored by that much: it should lead to a record of 13-15, so it could be said we were a tad unfortunate. We had a winning record in games decided by five runs or more, but only went 1-4 in one-run games - this is the reverse of what we did for much of last season.

I should also probably look and see what our direct rivals in the NL West did over the same period - that's quite comforting, because it turns out that May pretty much sucked for all of them as well. The best record anyone managed to put up was the 13-15 posted by the Dodgers, and it was all downhill from there, to the 9-19 returned by Colorado. The Los Angeles offense had a particularly woeful month, with a collective line of .253/.312/.356, an OPS 63 points worse than Arizona's. Even allowing for park factors, you won't score too many on less than two extra-base hits per game. And, hey presto, the Dodgers had an NL worst 111 runs in May.

Not that we exactly did a great deal better - only six runs, in fact, and there seems little doubt that it was at the plate that the Diamondbacks struggled. In April, they hit .268/.345/.468 for an OPS of .813; for May, the same figures were .244/.328/.402, and the OPS dropped all the way down to .731. As a comparison, the league average OPS was .736 in April and .751 in May, so the Diamondbacks not only got worse, the rest of the hitters in the National League heated up. Hence, we dropped all the way down from second to thirteenth overall, and if you took park factors into account, we could be even lower than that. Let's take a deep breath and see which of our hitters had the worst dropoffs: the table below covers all who had 50 or more plate-appearances in either month (which is, conveniently, the same players, basically our regular starting eight for these two months):

This illustrates a few things. Most obviously, the complete collapse of Eric Byrnes as an offensive contributor in May - he went from adequate to utterly horrible. However, his drop-off was almost matched by Conor Jackson, though the starting point for CoJack was a good deal higher: he went from insanely hot to mediocre. The news that he's been carrying a quadriceps injury causes me concern here: is this another case of someone playing hurt, regardless of impact on the team? However, at least the return of Tracy has given us a decent (thus far) alternative, which wasn't perhaps seen as the case with Byrnes - though if Salazar couldn't beat a .477 OPS over a month, I'd wonder what he was doing on the roster.

Further down the list, we find Reynolds and Upton, who struggled mightily in the middle of the month, but both showed some signs of life at the end. Drew and Young have been consistent, particularly the latter, whose K:BB ratio is basically the same in both months, at 2:1. However, Drew's had changed radically: in April he had nine walks and twelve strikeouts, but for May, he walked just three times and fanned 22. The mild drop in OPS for him is almost entirely due to this, since his slugging percentage remained basically unchanged, .483 to .486.

Snyder and Hudson carried the team offensively over the past month, and we can only hope that they will continue this into June. However, their BABIP in May were .400 and .418 respectively, and it's going to be hard for them to replicate that over any long period of time. Young and Jackson, at .259 and .253 respectively, are perhaps most likely to benefit from balls dropping their way in the next month. Byrnes was an even worse .161, but we have no idea when he'll be seen again, or whether he will be as acceptably effective as he was in April.

We can do something similar with our pitchers, though overall, the drop-off was less significant. ERA did increase from 3.25 to 4.09, but even the latter figure was still good enough for the third-best ERA in the National League. After we'd led the NL in April, this month we were bested by both Atlanta and Chicago - something of a feat as all three teams' parks are ranked among the five most hitter-friendly in the major-leagues. Splitting the ERA up among our starters and bullpen is particularly interesting: it shows the latter were much less effective in May. The rotation ERA increased somewhat, from 3.62 to 3.94, but the relievers exploded from 2.58 to 4.48. Their OPS against shot up from .575 to .734, with hitters batting 65 points better, at .258, compared to a sub-Ueckerian .193 in April. Our bullpen was 0-6 last month and have only one win - Medders on April 30th - in the last forty games.

Here's the chart comparing ERAs for April and May. As you should all know, ERA is not a particularly good tool for looking at relievers and judging their effectiveness, but it probably is not too bad for Arizona, since Melvin likes to use his relievers for clean innings, where possible. The cutoff on this chart is ten innings.

While Qualls and Cruz both likely over-performed in April, their fall from grace in May were pretty spectacular. Cruz, in just ten innings, had eleven walks and nineteen strikeouts, so it was all or nothing with him; Qualls simply allowed a lot of hits, sixteen in 10.1 innings, compared to a mere six in 15.2 innings during the previous month. On the plus side, Johnson improved his K:BB ratio from 22:9 to 34:5, and as a result his opponents' OBP decreased from .344 to .299. Peña reined in the hits, reducing OBA 94 points to .200, and his ERA benefited immensely from that.

Not included is Brandon Lyon, as he pitched only eight May innings, and a mere three of those were in save opportunities - the last one all the way back on May 15. However his ERA dropped from 2.57 to zero, and Lyon now has not allowed a run or an extra-base hit in nineteen innings since April 6. Similarly missing is Max Scherzer, who had 4.1 April innings - albeit perfect ones in his debut - but both men will clearly play an important role in the bullpen going forward.

Past performance is no guarantee of future success - on the other hand, those who forget the past are condemned to repeat it. May pretty much sucked, but we caught a break, with everyone else in the division sucking too: the schedule in June is not exactly a cakewalk, and we'll need to play a damn sight better if we want to remain in first place at the end of the month. At least we started on the right foot, with a victory today; hopefully, we can continue on that route for the next few weeks.