Marcus Semien is breaking out at the plate

The Oakland A’s are currently just one game out of the last AL Wild Card slot, and they are projected to finish with over 90 wins for the second straight season. Matt Chapman has become the face of this franchise after his MVP-caliber breakout last year, but he is now getting competition from Marcus Semien for best player on the team.

Semien was drafted by the Chicago White Sox in the sixth round of the 2011 draft. He made his major league debut just two years later, but it did not go very well. He played only 85 total games at the major league level through the 2014 season and hit .240/.293/.380, which is not bad for a shortstop, but his defense was not great. The White Sox appeared to believe that Semien was never going to be anything more than a below average overall shortstop, so they traded him to the A’s after the 2014 season in a deal that brought Jeff Samardzija to Chicago.

Semien’s first year in Oakland was more of the same. He hit .257/.310/.405, good for a 97 wRC+, which again, is pretty good for a shortstop, but unfortunately, he continued to struggle defensively. He actually had a 5 DRS that year, but his -11.7 UZR more closely aligns with the eye test. As a result, he had only 1.4 fWAR that year despite being a fair hitting shortstop.

The A’s understandably did not want to give up on Semien at shortstop. You might be familiar with what happened next, as was described here by Kenny Kelly. The A’s brought in former Rangers manager Ron Washington to help with his defense. Wash might not have been the best manager — well, certainly not tactically, at least — but he has always been a great assistant coach.

Semien’s defense did not improve overnight, but he worked very hard, and it did improve with time. He had a -6.2 UZR in 2016 and a -3.5 UZR in 2017. Finally in 2018, he jumped all the way to a +8.3 UZR. His fielding probably improved by two full grades over the course of a few seasons! His offense remained the same, though, but that defensive boost made him worth 3.7 fWAR for the 2018 season.

Now Semien has improved just as much offensively. He is hitting .271/.357/.476 with 21 HR, which combine for a .351 wOBA that is 44 points better than the year before. His 122 wRC+ ranks fourth among qualified shortstops, though two of the players in front of him, Alex Bregman and Gleyber Torres, have primarily played other positions this year.

Semien has both drastically improved his plate discipline and contact rates. He walked at a league average rate for his career, but now he is walking 11.7 percent of the time. As for his contact rates, he was always better than average in that area, and now he is only striking out 14.4 percent of the time, which ranks him in the best 30 in baseball among qualified hitters. He is also doing more damage when he makes contact. According to Baseball Savant, his hard-hit rate and exit velocity are up.

It is great to see Semien’s relentless work ethic pay off. It is also great to see that the A’s are not letting it go to waste, as they are in the playoff hunt this year and should be again next year. After that, however, Semien will be a free agent, and even though it is hard to predict what free agency will be like in two years, if he keeps playing like he is now, he will command a big contract that the notoriously cheap A’s will likely not want to pay.