Much of the Oakland Athletics' success this season has stemmed from manager Bob Melvin's implementation of platoons in the field. Quality players like catchers John Jaso and Derek Norris split time based on the opposing pitcher's throwing arm.
Jaso would hit against righties, Norris would hit against lefties, and everyone's knees stayed well-rested. That worked until Stephen Vogt was called up from Triple-A Sacramento and proceeded to mash the stitches off the ball, forcing Melvin to keep him in the lineup, though often away from his natural position.
An overflow of talent is certainly not a bad thing, especially considering the physical demands that tax everyday catchers and can diminish their offensive production. But there are only so many innings to share among Vogt's hot bat, Jaso's Moneyball skill set and Norris' impressive all-around game.
94 G, 295 AB, 41 R, 8 HR, 38 RBI, .264 BA/.340 OBP/.424 SLG
When the baseball gods craft a low-budget No. 2 hitter in the future, they can use Jaso as the prototype. Blessed with a keen hitter's eye, solid gap power and above-average baserunning skills, Jaso is general manager Billy Beane's kind of player.
Jaso missed half of last season with lingering effects from a concussion on July 24, 2013, and his 34 games as the A's designated hitter this year are more than any other player on the roster. His offensive numbers are good for a catcher but seem average when compared to other DHs.
Oddly enough, Jaso hits much better when playing catcher than DH-ing despite the extra workload associated with playing in the field. He's batting .296 as a catcher and .226 as a DH since he began splitting time between the positions in 2012.
DH-ing Norris or Vogt would make sense if Jaso were a better defensive catcher, but his limited skills behind the plate argue otherwise. He's thrown out just four of 35 potential base stealers this year and has cost the A's four more runs defensively than a league-average catcher, according to FanGraphs. In fact, Jaso's fielding and positional adjustment combined value ranks dead last among catchers with 160 plate appearances or more in 2014.
92 G, 269 AB, 35 R, 10 HR, 47 RBI, .286 BA/.379 OBP/.457 SLG
There's a reason Norris caught A's closer Sean Doolittle in the 2014 All-Star game. He has elevated his game to become one of the league's best receivers this year despite splitting time behind the plate.
After a rough offensive start to his career, Norris has blossomed in his third season with Oakland. His .834 OPS is the best on the team among players with at least 200 at bats, and he has stepped in as the cleanup hitter against left-handed pitchers after Yoenis Cespedes was traded.
Some of the success for Norris' career-best slash line can be traced to his diminishing strikeout percentage, which has tumbled from 28.4 percent in 2012 to 17.9 percent in 2014.
Like Jaso, Norris doesn't throw out many guys on the bases (seven of 47 runners this year). But his offense is good enough to earn a cumulative 2.6 WAR, third among American League catchers.
Norris came over as a prospect in the Gio Gonzalez trade back in 2011 alongside pitchers Brad Peacock, Tom Milone and A.J. Cole. Coincidentally, Cole was later traded back to the Washington Nationals in the deal that brought Jaso to the A's.
57 G, 194 AB, 21 R, 7 HR, 29 RBI, .325 BA/.356 OBP/.495 SLG
Calling Vogt a catcher is getting to be a bit of a stretch, since he has mainly played first base and right field after being called up at the beginning of June. That's a testament to his versatility and the established veterans already behind the plate, not a reflection of Vogt's defensive skills.
Though he has logged just 85.1 innings behind the plate this year, Vogt has thrown out just one fewer baserunner than Jaso on the year, with no stolen bases against him so far. Vogt also threw out 31 percent of base stealers in a more permanent role behind the plate in 2013.
Vogt was one of the hottest hitters in the majors for about 40 games after being called up, peaking with a .376/.407/.564 line on July 11. He's regressed somewhat since his out-of-this-world start, but his 1.7 WAR is higher than Jaso's despite having spent two months in the minors.
The one drawback to Vogt's offensive production, other than being a typical slow-footed catcher, is he doesn't work pitchers like many other Athletics, including Norris and Jaso. His batting average is on par with hitters like Victor Martinez and Adrian Beltre (again, in a small sample size), but his on-base percentage is more along the lines of Christian Yelich and Denard Span.
The current platoon is working out well for the A's, so there's no reason to bat Norris more against right-handers or Jaso and Vogt against southpaws. All three have harsh righty-lefty splits and are best suited in their current roles.
Norris has emerged as a legitimate star this year, while Jaso is a solid role player but just that. Vogt is probably most valuable as a utility bat who can slide behind the plate as a late-game defensive replacement.
All advanced statistics courtesy of FanGraphs.