Including his performance with the Yankees, Brian McCann has a career slash line of .274/.345/.466 (115 wRC+). When the Yankees signed him in the offseason, the thinking was that he would produce along those lines, combined with excellent defense and pitch framing. The team got the latter two, but not the former. From the beginning of the season to July 8th(309 PA--I'll get to the date later), Brian McCann hit .231/.288/.378 (83 wRC+) with just seven home runs. That was in stark contrast to his ZiPS projection of .258/.340/.451.
Of course, the criticisms began to crop up. There was those infamous comments from McCann's former hitting coach Terry Pendleton that he couldn't handle New York, that the pressure hanging over his head due to a large contract in a large market would doom him. Ben Lindbergh of Grantland did a bit of research on this and found that most of the criticism was bunk. McCann was not pulling his way into the shift, his approach had not changed, and his plate discipline was consistent. The only issue that arose was with his hard-hit average; the type of power he had seen in the past wasn't cropping up.
Luckily, there was a possible solution. Kevin Long worked with McCann and eliminated the toe-tap in his swing, something that Long believed screwed with his timing. Well, did that work? Since that article on the toe-tap was published on July 8th (remember that date?), McCann has hit .300/.328/.383 (96 wRC+). Is that explosive? No, it's not. It's not in line with his career mark nor with his ZiPS projections, but it's still in stark contrast to pre-July. The contact is now there; it's just the power that is missing. Could this be because of some of the issues that Kevin Long found when ironing out McCann's approach? That's possible. I'd say it's probably luck. Here is the spray chart of batted-ball data from 2012 and 2013 via FanGraphs:
And what does that look like this year? Pretty darn similar:
The obvious tendency to favor the right-side of the field is still there--fly balls just haven't found their way over the short porch as of yet. But like his overall batting line, that will certainly regress.
To think that the first half of the season is a true barometer of McCann's performance is completely ludicrous. Players that have the type of track record McCann has do not turn into a pumpkin overnight, especially when it has been proven that everything that made him successful in the past has remained the same. The issue is that people confuse performance with talent.
For example, let's take a look at Baseball Prospectus' PECOTA projections for Brian McCann. What's great about these projections is that they don't just show you the projection, but every possible projection given their expected talent level. And if you take a peak at McCann's 10th percentile PECOTA projection, it reads: .222/.297/.391. Does that look familiar? That means that given McCann's talent level, there is a 10% chance that he would perform at that level or lower. What we were seeing was that 10% chance. If his performance was beyond the realm of possibility then I would be worried. But if we were to run 100 simulations of McCann's 2014 season, about 10 of them would look like his current performance, or worse. It'd be the same player that could possibly hit .288/.374/.508 (the 90th percentile). Both of them would be equally deceptive, but the talent level would remain the same.
Brian McCann is essentially the same hitter he was last year. There's the obvious discount one would add for a year of aging, but he is not a significantly different hitter. He has improved in the past month due to some changes, changes that have put him more in line with his expected performance. It's not there yet, but you can see regression happening. The days of ~80 wRC+ McCann are behind us, I believe, and what we will see in the future is the player we all expected coming into this season.