Josh Thole and that other Dickey Effect

Over the last three years with the Blue Jays, Josh Thole has posted a .212/.283/.258 triple slash line over 337 plate appearances, accumulated mostly while catching R.A. Dickey. While he appears to be quite good at doing so, that lack of offensive production negates a significant amount of value added defensively. So I was not terribly impressed when the Jays picked up his 2015 option last November, and I listed him as a non-tender candidate for this offseason. Russell Martin seemed to do a decent job catching Dickey, and even if they wanted a personal catcher, surely there's others who can catch a knuckleball and provide more punch at the plate.

But it turns out that having Martin catch Dickey might not be such a great idea after all. Kyle Matte of Capital Jays found that in the 21 games when Martin caught Dickey, his offensive production absolutely collapsed, with a smaller day after effect. We all know about the good "Dickey Effect", but it appears there might be another opposite effect additionally.

After reading that, my thought process went something like this:

1. Holy batman!
2. Pretty small sample size, need to test for significance
3. Maybe this explains what happened to Josh Thole's bat

Thole was not always a terrible hitter. Coming up through the minors, he was a good hitter with a pretty consistent profile from his first full season in 2007 through the upper minors. He showed little real power but an ability to spray singles and doubles, and combined that with strong plate discipline, walking roughly as often as he struck out.

That profile and production carried over to the majors. From his debut in September 2009 to May 7, 2012, Thole logged 764 plate appearances, posting a .277/.351/.358 line that was good for a 98 wRC+, almost exactly league average. He walked 10% of the time, struck out just under 12%, had a .308 BABIP and a .081 ISO. But it was on May 7 that his season—and who knows, maybe his career—was derailed by a concussion that caused him to miss three weeks.

For the rest of the 2012 season, he was a completely different hitter: he walked less (7%), struck out more (15%), struggled to get hits (.256 BABIP), saw his already low power go to even more anemic levels (.045 ISO), a 47 wRC+. Given the struggles of other players coming back from concussions, this was understandable. So when the Blue Jays acquired him, there was obviously the angle of catching Dickey, but also the potential of being a longer-term quality starting option.

Opening 2013 in Buffalo, it seemed like Thole was over his struggles, as he mashed .322/.383/.510 over the first two months of the year earning the call-up as J.P. Arencibia's OBP collapsed. Unfortunately, Thole couldn't take advantage of this opening, posting similar numbers to post-concussion 2012: an Arencibiesque OBP without his power, a brutal 38 wRC+.

In 599 PA since June 2012, Thole has been a .214/.279/.260 hitter, 50 wRC+. He's walked a decent rate (8%), but his strikeout rate is much higher than before (16%) with no power (.046 ISO) and without getting hits to fall in (.258 BABIP). For five-plus years, he had a consistent and quite successful hitting profile. Then it's like a switch flipped three-and-a-half years ago and he hasn't hit at all since.

But 2012 also coincided with the rise of R.A. Dickey, and since then a larger portion of Thole's time behind the plate as been catching Dickey. Perhaps, like with Martin, dealing with the knuckleball has exacted a toll on Thole's hitting. So I compiled the results, and they were not at all what I expected:

Unlike Martin last year, Thole has overall been a much better hitter when catching Dickey. Across his career, the difference has been 50 points of batting average, 40 points of OBP, and 80 points of slugging. That wOBA differential of 0.047 works out to about 20 runs over 600 plate appearances.

It's worth pointing out that the strongest differential years with the biggest samples were back in 2010-2011, and so perhaps not terribly indicative of what to expect especially since he's been a very different hitter since. But even out the last four years only, there's a wOBA gap of .029, which is about 14 runs over 600 plate appearances.

Granted, a .267 wOBA is still pretty bad, but it compares quite favourably to Martin's .241 wOBA when catching Dickey in 2015. Even if we assume a learning curve for Martin and/or some regression and said they were equal true talent hitters when catching Dickey, I'd still rather not see our 33-year-old catcher with 10,000 MLB innings behind the plate and owed $75-million over the next four years being worn out by Dickey. Keeping Thole as the backup at a $1.8-million salary would actually be pretty good value, even if it also meant him starting another 15-20 day games after night games.

Ideally, the Jays would be able to find a better backup who can catch the knuckleball and hit a little more then Thole has. George Kottaras in particular is very interesting, as he has hit in MLB (100 wRC+) and has experience catching Tim Wakefield in 2009. But, in any event, I have a renewed appreciation for Josh Thole, though I'd still like to know why his bat went so far backwards so suddenly.