A quick look at Mariners righty/lefty batting splits

It's no secret that the Mariners offense in 2014 was... a little sad. Despite the enormous offseason addition of Robinson Cano, the Mariners only managed to score 10 more runs than they did in 2013 (and actually put up inferior OPS, wOBA, and wRC+ values). This certainly wasn't Cano's fault; the blame seems to rest mostly upon his teammates who batted from the other side of the plate. The following table takes a look at the righty/lefty batting splits for the Mariners last season.

Mariners lefties put up respectable numbers against left-handed pitchers in 2014 and were quite good vs. righties with the fifth highest cominbed wRC+ in all of baseball. This was largely driven by the fact that their three best hitters (Cano, Seager, and Saunders) are all left-handed, but Morrison (wRC+ 110), Chavez (wRC+ 97), and Ackley (wRC+ 97) each had respectable numbers, too.

However, from the right side of the plate, the Mariners struggled mightily. As a team, they ranked dead last in wRC+ and OPS against both right-handed and left-handed pitchers. The following charts show where the M's regular/semi-regular righties ranked, in terms of wRC+, among right-handed MLB batters last year:

Switch-hitters who batted right-handed are also included in these plots.

Chris Taylor was slightly above average against right-handed pitching (with a wRC+ of 100), but everyone else was fairly lousy. Below, to give a more complete view of their numbers, I've listed the men that had 90 or more PA from the right side of the plate for the M's in 2014. These stats reflect their performance against both right-handed and left-handed pitchers.

*Switch-hitter batting right-handed against LHPs.

Out of these 10 players, five will not/better not be with the Mariners in 2015. Morales, Smoak, Hart, Buck, and Denorfia combined to hit .213/.278/.327 from the right side in 2014 in ~600 PA. Their departures will be sorely missed. I sure hope that the Mariners upper management is able to fill so many crucial, productive holes...

As for the players who are still with the team (as of today):

• Taylor's numbers (obligatory SSS reminder) look okay at first glance, but when you recall that they're fueled by a not-so-sustainable .398 BABIP, it's hard to get too terribly excited about them (he was basically a version of Willie Bloomquist that walked at a league-average rate last season). That being said, Steamer does project Taylor to be a ~league-average hitter going forward (wRC+ of 96), so he probably won't regress too dramatically.
  

• Zunino accounted for about a quarter of the right-handed at bats by Mariners last year, and while he certainly has ample pop in his bat, there are a lot of holes in his swing right now. I'm still not entirely comfortable counting on him as a regular offensive contributor.

• Willie Bloomquist is Willie Bloomquist. The Mariners will pay him $3 million to continue to be Willie Bloomquist next year. (Despite being Willie Bloomquist, Willie Bloomquist was actually significantly better than the average right-handed bat for the Mariners last year. Yikes.)
  

• Romero managed to accumulate 190 PA in 2014. Unfortunately, his relatively disastrous performance suggests that it'll probably be difficult for him to receive the same opportunity next year (unless he really sets fire to the PCL, but he's already done that so I don't know). Of course, the Mariners current bench situation is somewhat in flux, so who knows.
  

• Jackson's overall offensive performance with the M's last season was uncomfortably similar to Romero's. Gross. He'll almost certainly put up significantly better numbers in 2015, which should help the Mariners a lot. (Steamer thinks he'll put up a wRC+ of 101, which is just below his career average.)
  

So, yeah. Mariners right-handed hitters were far from dominant last season. Another stat that reinforces their offensive impotence was that in 2061 PA last season, M's righties were intentionally walked THREE times. This is the fewest number of IBBs issued to a team's right-handed hitters. The Cubs had the next fewest with seven IBBs. For reference, both Dominic Brown (wRC+ of 75) and Andrelton Simmons (wRC+ of 71) were intentionally walked more often (four times each).

Looking ahead to next year, it shouldn't be difficult for the Mariners to see an increase in production from their right-handed hitters. Jackson should be a lot better and Zunino's wRC+ is also projected to increase from 86 up to a near-league average of 94. Seattle has also been tied to basically every right-handed bat on the market, from Nelson Cruz to Billy Butler to Hanley Ramirez. It's probably a safe bet that any of those gentleman would post a wRC+ above 73. The Mariners lineup should be a bit more balanced moving forward.

Folks have been clamoring for a long time for Seattle to add a "right-handed bat" to their roster. I think that it's definitely a bit narrow-minded to focus on such a specific method to try and improve this team (the Mariners should be looking to add production/value no matter where it is!), but the reasons behind this somewhat silly demand are not entirely unfounded. The last Mariner regular right-handed batter to post a wRC+ north of 100 was Franklin Gutierrez back in 2009 (there have been five such left-handed players during that same span). It's been several years since the M's have had anyone particularly menacing step into the right-hander's batter's box, so the frustration is understandable. Looking at how this off-season appears to be shaping up, the Mariners may finally go out and buy a right-handed bat.