The Seattle Mariners couldn't buy a walk in 2011. The M's had the second-lowest rate of free passes taken (7.3 percent) among AL clubs and, in a related note, placed dead last in on-base percentage (.292) and runs scored (556). Seattle's newest acquisition, John Jaso, should provide the M's with some much-needed plate discipline. The lefty hitter, picked up from Tampa Bay for reliever Josh Lueke, couldn't be more different than the man he'll now platoon with, Miguel Olivo.
During his major league career, Jaso has swung at just 34 percent of the pitches seen. Only Luis Castillo, Nick Johnson, Bobby Abreu and Brett Gardner have pulled the trigger less often among hitters with 500+ plate appearances from 2008-2011. He has chased 20 percent of pitches thrown out of the strike zone, one of the lowest 20 rates among MLB hitters. Check out Jaso's swing rate by pitch location, compared to the league average. Unless it's high and tight, he's probably keeping the bat glued to his shoulder:
The exception to Jaso's ultra-passive approach is two-strike situations. When the pitcher has him down to his last strike, he swings about 57 percent of the time. That's still below the 61 percent average in such situations, but not by a whole lot. And when he swings, he rarely comes up empty: Jaso has a 12 percent miss rate both in two-strike counts and overall, compared to the 20-21 percent MLB average in both situations.
By working deep counts and avoiding strikeouts, Jaso has walked more than he has whiffed (12.1 BB%, 11.4 K%). That has allowed him to get on base at a .340 clip and be a league-average hitter (101 wRC+) despite possessing little pop and posting a mid-.260s batting average on balls in play indicative of a slow-footed backstop. If you're holding off a bathroom stop or a beer run for a Jaso at-bat, you might be a while.
With Olivo, on the other hand, you'll be at the stall or sipping a Coors in no time. The righty batter has swung at about 57 percent of pitches seen since 2008. Pablo Sandoval, Delmon Young, Jake Fox, Vladimir Guerrero and Humberto Quintero are the only 500+ PA hitters to take a cut more often. And Olivo's 41 percent chase rate is surpassed by that of only Fox, Mark Trumbo, A.J. Pierzynski, Sandoval, Guerrero and Quintero. If it's anywhere near the dish, Olivo starts salivating:
With two strikes, Olivo has swung 68 percent of the time over the past four seasons. While Jaso avoids the Ks, Olivo has swung and missed 35 percent of the time in two-strike counts and 36 percent of the time overall.
With such a hack-happy approach, Olivo has struck out over six times as often as he has walked in recent years (4.4 BB%, 27.9 K%) and has a .283 OBP. His only redeeming feature at the plate is that he'll hit some moon shots in between all of those outs, making him a passable bat for the position (86 wRC+).
Assuming Jaso gets the bulk of the ABs, the trade with Tampa should work out pretty well. Jaso gives the M's a hitter with a with a clue at the plate and limits Olivo to a lefty-lashing role he's best suited for (he's got a career .277/.311/.487 line in 1,030 PA against lefties, compared to .229/.265/.395 in 2,535 PA against right-handers). Just don't expect Jaso and Olivo to share too many batting tips with each other.