Series Preview: Seattle Mariners @ Oakland Athletics

These might morph a little bit as the season goes on. I haven't hit upon any obvious improvements I want to make over how they ended last season, but I am rarely ever satisfied with the status quo. To the new people or those who forgot how these work over the off season here's a quick rundown.

At the beginning of each series I will grab the current team ratings and rank in a variety of categories that I feel best encapsulate the four talent areas. The offense rating comes from park-adjusted wOBA as listed on StatCorner. Similarly the rotation and bullpens come from park-adjusted tRA as seen on StatCorner. The fielding is always the stickiest wicket but for now will remain the weekly updated UZR on FanGraphs. I'd ultimately like to get something that updated daily, but none of the systems that do that are centered until after the season ends.

The first column will list the current amount of runs above or below average that the Mariners are in each category along with their rank out of 30 teams. The second column (Δ Ms) will show the increase or decrease since the beginning of the last series. The third column is a repeat of the first but for our opponent and finally the Edge column is simply a comparison between the two teams.

After the chart and some general discussion on how the games went in the last series comes the preview of the upcoming starters. This will also require some explanation so pull out your strategy guides and turn to appendix B. As a quick note, I just realized that the red and green bars are next to each other so preemptive apologies to the red-green colorblind. I'll try to fix that for next time.

Fri 01 April 19:05
FELIX HERNANDEZ	TREVOR CAHILL

You might remember the pitcher charts that were present throughout all of last season. I still think they're nifty, but am always trying to find more compelling ways to present the data behind them rather than just listing numbers. Who likes looking at numbers? Accountants do; and who likes interacting with accountants? Nobody. Instead, everyone flocks around the artists who get to captivate audiences with drivel about how much puce reflects their inner soul's past lives. Lousy beatniks.

Anyways, here's the deal with the above graphs. I group each pitch type thrown by each pitcher over the past couple years and compare them against the results in three categories that the rest of the league gets on the same pitch type. Felix's fastballs get compared against everyone else's fastballs and so on down the line. The three categories are missing bats (swinging strikes), throwing strikes and getting ground balls when they are put into play. To me, those are the three essential skills for a pitcher.

I take each pitch type and manipulate the league's results onto a 20-80 scale with the help of the Dark Lord Mathematics. Why this weird scale? Because it's the same scale used by scouts and is common jargon when discussing tools on players. Essentially, that's what this is all about; breaking down a pitcher's repertoire into individual pitch tools. You can see where each pitch falls on the 20-80 scale with the vertical bars.

Keep in mind that pitches are judged according to other versions of the same pitch. If you look at Trevor Cahill's graph, you'll notice that his fastball rates higher on the ground ball scale than his sinker or change up or curve ball do. That doesn't mean Cahill's ground ball rate on fastballs is higher than it is on sinkers however. It means that Cahill's fastball gets more ground balls compared to other fastballs than his sinker gets compared to other sinkers. Everything on the graphs is relative.

The key at the top tells you which pitch is which. They are ordered from left to right by most to least frequently thrown as shown by the first number following the pitch type. The number after that is the average speed of the pitch. The final black vertical bar represents the pitcher's overall ranking in the category. It is a weighted average. For Felix Hernandez, if he were to be graded on his current skills as a pitcher and the grader had a keen mind able to tell exactly where all other MLB pitchers were, said grader would award Felix with a 75 in getting strikeouts, a 65 in avoiding walks and an 80 in keeping the ball on the ground.

Needless to say, those are phenomenal grades. Take a jump below to see an example of just how much more dominant Felix is than the other five pitchers going in this series.

Sat 02 April 18:05
JASON VARGAS*	BRETT ANDERSON*

What I really enjoy about these other than gazing at how much fuller Felix's bars are than everyone else's is how it can help identify out pitches at a single glance. Looking at Jason Vargas's chart it should be immediately clear that without his change up he would be out of baseball or at least much worse at it. 

Brett Anderson wouldn't be so hard up without his curve ball but it is clearly his best pitch and without it he would be rather awful at getting strikeouts. 

Sun 03 April 13:05
DOUG FISTER	GIO GONZALEZ*

Yeah, Doug Fister doesn't miss bats, but he makes up for it by avoiding walks and not being totally averse to ground balls. We all know that, but it wasn't readily apparent to me that Fister never threw his curve ball for strikes. It is, however, his best pitch at inducing a swing and a miss and even when contact is made, stays on the ground better than anything else he lumbers up to the plate. Looking at the speed might be why as a 74mph curve ball is usually a big looping one. Aside from the affinity for ground balls, Gio Gonzalez and Doug Fister are near opposites. 

All three of Oakland's pitchers are devoted groundballers. Trevor Cahill and Anderson both have overall 80 ratings and Gonzalez at 70 is certainly no slouch. That's an interesting collection given the home park effects in Oakland which help to suppress home runs, but does lend itself to caution if you were hoping for the Mariners offense to sprint out of the gate with an outburst of power for some delusional reason. The strategy for Seattle should be to try and work walks when possible and get enough runners on base that some of them score out of sheer inattention on Oakland's part.