When theretofore ordinary second baseman Daniel Murphy turned into the reincarnation of Babe Ruth during last year’s playoffs, it was a fun story. Murphy was with the New York Mets through their lean, mediocre post-Madoff years, and he was suddenly the driving force behind their surprise World Series run. It seemed proof that in a handful of baseball games, damn near anything can happen.

But for the sabermetrically minded (which presumably included the Mets’ front office), Murphy was still the decent-but-not-great player that his overall record said he was, and at age 30, he was likely on the downside of his career. So during the winter, the Mets moved on from Murphy to Neil Walker at second base — which, according to the stats, was basically the right call. Murphy signed with the Washington Nationals instead, and although projections suggested that he would have a solid season, there didn’t seem to be any way that he would build on his outlier postseason performance.

Those projections have turned out to be flat-out wrong. Instead of reverting to his previous form, Murphy has looked an awful lot like the guy who went on that postseason tear: He currently ranks third in the National League in Weighted Runs Created Plus (wRC+) and fourth in wins above replacement. (Murphy has also hit Mets pitching especially hard this year, delivering what already ranks as the most RBIs by a player against a team he played for the previous season since 1960.)

For a guy who has never ranked higher than 37th in WAR, Murphy has taken a quantum leap forward. If Murphy maintains his current wRC+ for the entire season, it will be the 21st-biggest single-season improvement by a hitter over his previous career wRC+ at age 31 or older since 1901:

SEASON PREVIOUS CAREER PLAYER YEAR OBP SLG WRC+ OBP SLG WRC+ WRC+ CHANGE Barry Bonds 2002 .582 .799 244 .418 .585 164 +80 Barry Bonds 2001 .515 .863 235 .411 .567 159 +76 Sammy Sosa 2001 .437 .737 186 .333 .523 119 +67 Ken Caminiti 1996 .408 .621 169 .328 .402 102 +67 Javy Lopez 2003 .378 .687 170 .332 .478 107 +63 Barry Bonds 2004 .609 .812 233 .433 .602 171 +62 Bret Boone 2001 .372 .578 149 .313 .413 88 +61 Luis Gonzalez 2001 .429 .688 173 .355 .460 114 +59 Paul O’Neill 1994 .460 .603 171 .341 .443 115 +56 Rickey Henderson 1990 .439 .577 190 .400 .429 136 +54 Mark McGwire 1998 .470 .752 205 .382 .556 152 +53 Dixie Walker 1944 .434 .529 168 .369 .434 115 +53 Mike Schmidt 1981 .435 .644 198 .375 .526 145 +53 Willie Stargell 1971 .398 .628 186 .341 .503 134 +52 Roberto Clemente 1967 .400 .554 170 .348 .455 118 +52 Brady Anderson 1996 .396 .637 155 .349 .393 103 +52 Lonnie Smith 1989 .415 .533 166 .362 .401 116 +50 Roy Cullenbine 1946 .477 .537 182 .402 .422 132 +50 Eddie Joost 1949 .429 .453 136 .332 .321 87 +49 J.T. Snow 2004 .429 .529 153 .353 .426 104 +49 Daniel Murphy 2016 .387 .598 157 .331 .424 109 +48 Jermaine Dye 2006 .385 .622 151 .334 .469 104 +47 Jimmy Dykes 1929 .412 .539 143 .356 .404 96 +47 Victor Martinez 2014 .409 .565 167 .369 .464 120 +47 Joe Morgan 1976 .444 .576 184 .396 .430 138 +46 Biggest hitting improvements at age 31 or older, 1901-2016 Only includes players with a minimum of 3,500 career plate appearances before season and 350 in season.

WRC+ = Weighted Runs Created Plus Source: Fangraphs

Many of the people atop that list — including (but not limited to) Barry Bonds, Sammy Sosa, Ken Caminiti and Mark McGwire — have admitted to using performance-enhancing drugs, were named in the Mitchell Report or were otherwise implicated in baseball’s steroid scandal via leaked test results. But nothing so sinister has been mentioned to explain Murphy’s rise, and some players outside the steroid era experienced similar (presumably natural) leaps in performance.

Murphy has always credited Mets hitting coach Kevin Long with making several key adjustments to his approach at the plate in an effort to help him hit for more power. Here’s Tyler Kepner of The New York Times last October, on Murphy’s swing changes:

“Long believed Murphy should harness [his] power by driving more with his legs, moving closer to the plate, getting his front foot down sooner and bringing his hands lower and closer to his body.”

The numbers bear this out: Murphy’s 2016 isolated power is 115 points higher than his previous career average, and he’s hitting the ball authoritatively in new areas of the strike zone. Murphy was always a solid hitter on pitches up and on the inner half of the plate, but his new approach has him driving the ball more on pitches in the middle of the plate and even ones low and away:

Of course, it’s still unlikely that Murphy has morphed into a hidden superstar after seven big-league seasons. Players in their 30s who improved on their previous career wRC+ by between 40 and 60 points in one season tended to lose 36 points of batting average, 38 points of on-base percentage and 80 points of slugging percentage the next year. But, on average, they were still better than they’d been before. Even a year after the initial breakout, they hit for a wRC+ 15 points higher than their career average had been beforehand.

That means Murphy probably is a better hitter now than he was in New York. And considering the damage he’s already personally inflicted on the Mets in head-to-head competition, it also means he may well end up being the key to an NL East title for the Nationals. Not bad for a player most thought would turn back into a pumpkin after his Cinderella story last October.

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