Mariners, A's eye upgrade with Morse, Jaso

Brad Mills/USA Today

Mike Morse's new home may not be the best fit for his swing. Each week, Stats & Information takes a closer look at notable MLB moves. This week's take looks at the three-way deal that led to new homes for Mike Morse and John Jaso.

Michael Morse Traded to Seattle Mariners

Morse is going to a Seattle team that sorely lacked right-handed power, ranking second-to-last in the AL in slugging percentage by righties. How much will Morse, who saw his slugging percentage drop by 80 points from 2011 to 2012, be able to help the Mariners?

One concern going forward is the decline in his pull-side power. After hitting 15 homers to left field in 2011, Morse last year managed just three left-field home runs and his slugging to left field was cut in half.

Michael Morse Isolated Power
By Direction

This decline in pull power was not a product of bad luck. Last season more than 80 percent of the balls he hit to the left side of the park were grounders and he hit just seven flyballs to left field.

The silver lining in this lack of pull power was an increase in opposite field power. His isolated power rose more than 200 points when hitting to right field and he led all right-handers last year in opposite-field slugging percentage and homers.

This increase in opposite-field power was no fluke. He also led all righties in opposite-field flyball distance and the percentage of at-bats ending in a hard-hit ball to right field.

Last year at Safeco Field not a single home run was hit to right field by a right-handed batter. This offseason the Mariners moved the fences in at Safeco. However, the right-field dimensions changed just four feet, compared to 12 feet in left field.

If Morse can't regain his pull-side power stroke in 2013, his impact on the power-starved Mariners might be minimal.

-- Katie Sharp

Oakland Athletics acquire catcher John Jaso

Three things to know about what the Athletics are getting with the acquisition of catcher John Jaso in the three-way deal that netted the Mariners Morse.

1. This is significant help in an area of need for the Athletics. Oakland catchers had a .204/.262/.325 slashline last season, ranking worst in the American League in all three stats.

Jaso will significantly boost that on-base percentage in particular. He had the eighth-best on-base percentage in the majors last season (.394) among those with at least 300 plate appearances.

2. That said, Jaso’s stats favor his usage against right-handed pitching only. His .164 career batting average against left-handers is the lowest of any active position player with at least as many plate appearances as Jaso has against lefties.

John Jaso vs Lower-Half Pitches

Jaso had a very good season against right-handed pitching last year, hitting .302 with 10 home runs.

That coincided with much improved performance against pitches in the lower-half of the strike zone or below, as the chart on the right shows.

Jaso’s .419 on-base percentage against righties last season trailed only Joey Votto, Prince Fielder, Joe Mauer, and Robinson Cano.

3. You may be giving up a little bit defensively. Jaso has -7 Defensive Runs Saved in his career, hurt by a 20 percent caught stealing rate that is well below the major league average of 27 percent.

But staff aces don’t object to throwing to him.

In two seasons with the Tampa Bay Rays, Jaso had a 3.09 ERA in 189 1/3 innings handling David Price (who had a 3.14 ERA with other catchers). Then last season with the Mariners, he caught Felix Hernandez 12 times. Hernandez posted a 2.50 ERA with Jaso (including a perfect game and a 1-0 shutout against the New York Yankees.) and a 3.42 ERA with others.

-- Mark Simon