When people discuss rookies in the American League, most of the discussion revolves around Luis Robert and Kyle Lewis. And for a very good reason. They are the frontrunners for ROTY in the AL as the dynamic center fielders have combined for 3.3 fWAR in just 325 plate appearances. But there is one other newcomer you should keep an eye on this year. He’s not going to win rookie of the year, but Sean Murphy’s game is as polished as any other, with both a high floor and a very high ceiling.
Coming into this season, Murphy wasn’t even the A’s top prospect coming into this season. He was blocked by the twin lefties Jesus Luzardo and A.J. Puk. But after Luzardo was delayed from making an appearance early in the season by a bout of COVID-19, and A.J. Puk yet to make his 2020 debut, Murphy has made a case that he is the best Athletics rookie right now.
For Murphy, it all starts behind the plate. He has already solidified himself as one of the game’s best defenders at a position where defense is the most important skill a player can have. His five defensive runs saved are tied for first among catchers. And by using baseball savant’s Runs Extra Strikes metric, which measures how many runs a catcher saves by getting extra strike calls, we find that Murphy is tied for third among catchers with at least 750 pitches called with one saved run. By multiple metrics, Murphy is already one of the top defensive catchers in baseball. You almost never see a player come up and instantly be a gold glove contender, let alone at a defense-first position. All in a day’s work for Murphy.
But glovework isn’t the only thing Murphy has impressed with. His time at the plate rather than behind it has also raised some eyebrows. Murphy carries a big stick and he is not afraid to swing it. His exit velocity of 91.6 MPH is in the 87th percentile and his hard hit rate of 52.6% is in the 96th percentile. His high quality of contact is reflected in his ISO, a mark of .202, which is currently 5th among catchers with 100 plate appearances. But even with his eye popping power, it is not what Murphy does when he hits the ball that impresses the most. It is what he does when he doesn’t swing the bat that is most noteworthy. Murphy’s walk rate is currently 8th among all hitters with at least 100 plate appearances. Not just catchers, all batters. Murphy has the 35th lowest swing rate on outside pitches and the 63rd lowest swinging strike rate. On their own these are not super impressive numbers, but they combine to make Murphy an elite walk drawer. It goes without saying that his combination of power and on base skills make Murphy a very good hitter, and his wRC+ of 132 backs this up. It is fifth among catchers with 100 plate appearances and second among A’s players. Pitchers don’t want to challenge Murphy because of his prodigious power, and Murphy can punish those pitcher’s cowardness with great plate discipline.
Murphy has a rare combination of power, defense and plate discipline that you rarely see in rookies, and while Murphy may not be ROTY, he is still playing at a high level and needs to be a player to keep an eye on. High quality defense and offense at an extremely important position will make Murphy very good for a very long time.