Managerial Smackdown: AJ Hinch vs. Kirk Gibson

It's now been just over a month since Kirk Gibson replaced AJ Hinch at the helm of the 2010 Diamondbacks, so it seems like an appropriate time to see whether the change has made any difference to the actual performance of the team. Has the bullpen stopped blowing as many chunks? Are the hitters waving at strike three less often? Is the USS Arizona now liming to port, or is it going round in circles while taking on more water? Are we fiery enough yet? After the jump, we'll take a look at the numbers, and see if there is objective evidence to point in either direction.

When looking at team stats and overall results, I only compare numbers up until July 28th, as on the 29th, Joe Saunders replaced Dan Haren. Almost universally regarded as a downgrade (though number so far have said otherwise), it wouldn't be fair to include games past that point, as Hinch and Gibson were playing with different hands. But up until then, they had basically the same players at their disposal, save the minor departure of Conor Jackson. We have over 850 PAs and almost 200 innings to work with for Captain Kirk, a respectable sample size with which to work. [Note: the decision was taken on that date, so no whining that I'm cherrypicking stats subsequently]

Win-Lost Record

On a straight up comparison, Hinch wins easily - his overall W% of .392 is clearly better than Gibson's .273 over the period in question. If we compare Hinch's last 22 games to Gibson's first 22, the gap expands, as Hinch's win percentage over that time was .409. But win percentage can be somewhat misleading - as we saw in 2007, the Diamondbacks creating an ocean of false expectations, posting the best record in the National League, when in hindsight, they really weren't.

We can also look at Pythagorean records, the projected ones based on the numbers of runs scored and allowed. Overall, under Hinch, the team scored 362 runs and conceded 446. That projects to a .397 winning percentage, very close to what was actually achieved. The same goes for his last 22 conters, where we scored 92 and conceded 111, a .407 W%. For Gibson, the numbers were 88-130, a Pythagorean percentage of .314. The slight improvement is caused in part by the team's decent record in blowouts (2-2 in games decided by more than six runs), but it still comes in below Hinch.

The relative strength of schedule faced by the two managers should also be examined. Based on their current record, Hinch came in for the season at .a 529 W% - he had a particularly brutal final stretch, however, and not one of his final 47 opponents currently has a losing record. In his final 22 games, the average W% went up to .570 - like playing the Red Sox every day - and bearing that in mind, the 9-13 record which resulted is actually credible. Gibson's number is .523, roughly in line with Hinch's overall strength of schedule for the year, so there's not any evidence he has a stronger schedule. However, 17 of his first 22 games were at home.

Of course, what we could be dealing with here is simply luck. If we assume the "true" talent of the team is their current win percentage, .374, then over a 22-game span, the chance of them winning six or less games (as Gibson did in his initial spell) is still about 23%. For the record to be statistically significant - say, at the 10% level - Gibson would have needed at least to post a winning record, or go 4-18 or worse.

Offense

There is clear evidence the offense has got worse under Kirk Gibson. Runs per game are down from 4.6 under Hinch, to exactly four now. Batting average and on-base percentage are close to the same, but the team is slugging about thirty points less. They had one home-run every 32.3 at-bats in the days of Hinch, but only every 47.3 in the Gibson era. We can't blame park factors for this drop-off, since as noted, seventeen of 22 games were in the cosy confines of Chase, where the Diamondbacks had, in the first 101 games, hit 140 OPS points better (.812 to .672). That should have led to an improvement in production, not the 15% drop in runs scored actually seen.

Maybe this drop off in power was the result of Gibson getting the team to cut down on their swings, stop going for the fences and reduce strikeouts? If so, that ain't working either. The K-rate has actually increased from 23.8% to 24.6% - and the walk-rate decreased fractionally. As a result, the K:BB ratio is up to 2.69 from 2.45. This may help explain why the number of runners left on base has been 7.7 per game, a ten percent increase from the number under previous management.

Another area of concern is the running-game. Gibson pressed the accelerator pedal, with 1.23 attempts per game, a big increase compared to the 0.73 figure under Hinch. However, the success-rate imploded from 78% to 62%, well below the break-even point of around 70%. About the only area that has shown an improvement in the stats above, is that we're grounding into fewer double plays - one every 71 PAs, compared to one in fifty under Hinch.

Pitching

There's hardly any change in the most important pitching metric, ERA. However, some of the peripheral numbers do indicate a slight improvement. Walk rate is down to 3.39 per nine IP, from 3.85 under Hinch, and strikes overall have moved from 62% to 65% - K rate has also gone up, from seven to 7.24. However, HR rate fractionally increased, going from 1.36 to 1.40. But perhaps the most obvious change is a sharp decrease in the percentage of inherited runners who scored, going from 46% all the way down to 31%.

That would likely require further investigation, because not all inherited runners are equal - letting a man score from third with no outs, is not as bad as letting him score from first with two outs. However, it does suggest something of an improvement by the bullpen under Gibson, and that is supported by a July ERA for our relief corps of 5.40, compared to an overall number during April-June of 6.98. However, this was almost exactly canceled out, by an increase in starter ERA from 4.64 under Hinch, to 5.14 over the opening month of the Gibson era.

Individual Performances

We all know that there are bosses for whom you do your best, and others for whom you give less than 100%, and there's no reason baseball managers should be any different. So, let's look at the numbers put up by our pitchers and hitters under Hinch and Gibson. Note we are definitely splitting thin down to small sample-sizes at this point, there's no real way to compare strength of opposition, and that if Player X does better/worse under Manager Y, that does not "prove" X loves/hates Y. I'm just curious to compare player performances and see what we can see, so don't read anything into this, m'kay? Stats here are through Tuesday, the "better" ones are bolded.

Conclusion

If Hinch was such a big part of the problem, as the nattering nabobs of AZ Central and their cronies perpetually proclaimed, then the team should presumably have got better when he was replaced - addition by subtraction. But there is little or no evidence that replacing Hinch with Gibson has had any positive impact on the performance of the team as a whole. Despite the predictable howls of delight from the expected circles at AJ's departure, it's hard to find anything in subsequent results to show that the undeniable issues with the 2010 Diamondbacks, were because of Hinch, or at least have been solved by his dismissal.