Corey Seager: From Prospect to Postseason


The following contribution comes from Bodie Dykstra. You can follow Bodie on Twitter @bodiedykstra.

When July turned to August and August to September, it appeared as though the Year of the Rookie may have left Dodgers top prospect Corey Seager behind. Along with Carlos Correa and Addison Russell, Seager was universally regarded as one of the top offensive shortstop prospects in baseball. Nevertheless, as the season wore on and Correa, Russell, and a historic number of other top prospects made their big league debuts, Seager continued to bide his time in Triple-A Oklahoma City.

The Dodgers did eventually promote Seager, and on September 3 he became one of the last names on a long list of major-league-ready prospects to appear in the show by the end of the regular season. Seager quickly demonstrated why named him the No. 2 overall prospect (behind Byron Buxton), hitting .337/.425/.561 with four home runs and 17 RBI in 27 games.

His performance not only earned him a spot on the Dodgers playoff roster but also the confidence of manager Don Mattingly. In fact, Mattingly has so much faith in Seager that for the first game of the NLDS he slotted the 21-year-old into the three hole in the batting order, a spot usually reserved for the team’s best overall hitter. Seager thus became the youngest player to start a postseason game for the Dodgers, an honor that caps off an incredible 2015 season that saw him advance from Double-A Tulsa to postseason mainstay.

Seager was drafted 18th overall by the Dodgers in 2012 and began his professional career as an 18-year-old later that season with the Odgen Raptors of the Pioneer League. In 46 games, he hit a solid .309 with eight home runs and 33 RBI. Seager split his first full season (2013) between Class-A Great Lakes and Class-A Advanced Rancho Cucamonga. He fared well in 74 games with Great Lakes, hitting for a similar batting average and slugging percentage as he did with Ogden. His first stint in Class-A Advanced did not proceed as smoothly. Through 27 games, Seager posted a .160/.246/.320 slash line, and although he managed to hit four home runs, he struck out 31 times in 114 plate appearances.

After struggling toward the end of 2013, Seager quickly found his swing again. He opened the 2014 season in Rancho Cucamonga and proceeded to destroy California League pitching; at the time of his promotion to Double-A Chattanooga, his 1.044 OPS was the best on the team by a wide margin and eventually came out as the third highest in the league by the end of the season.

Seager began 2015 ranked as the 13th top prospect according and the 5th top prospect according to Baseball America. In the words of, his “smooth, balanced lefty swing as well as bat speed, strength and mature all-fields approach” allow him to hit for both average and power in spite of a sometimes overly aggressive approach. Even though Seager was listed as a shortstop and possessed the instincts to play that position, scouts regarded him as a natural third baseman due to his size (he stands 6’4” tall) and relative lack of lateral speed.

All the same, Seager opened the 2015 season as the starting shortstop for Double-A Tulsa (the Dodgers switched affiliates in the offseason). He terrorized the Texas League with his bat and hit .375 with a 1.082 OPS, five home runs, seven doubles, and 15 RBI in 20 games. The Dodgers quickly promoted Seager to Triple-A Oklahoma City on May 1, and after initially staying hot in the hitter-friendly Pacific Coast League, he eventually slowed down by mid-season. He still finished the year with a respectable .278 batting average, but his power numbers were noticeably down as he slugged only .451, the lowest of his minor league career outside of his first stretch with Rancho Cucamonga in 2013.

Seager’s mediocre numbers in Oklahoma City played a part in his being passed over for promotion in July and August. With veteran shortstop Jimmy Rollins contributing well enough offensively and third baseman Justin Turner hitting his stride, the Dodgers brass saw no reason to move Seager up, especially if it meant denying the youngster regular at-bats or playing time in the field to develop his defensive skills. The Dodgers wisely held off until the Triple-A season was over and MLB rosters expanded on September 1.

While it was no surprise to see Seager in a Dodgers uniform in September, a Rollins finger injury suddenly thrust him into a starting role. Seager was called up on September 3 and made his Dodgers debut that same day against San Diego; he started at shortstop and batted eighth. After striking out looking in his first plate appearance, Seager got his first big league hit in the top of the fifth inning with a double down the right field line. His first two RBI came in his next at-bat when he drove in Carl Crawford and Yasmani Grandal with a single to center. Seager later smacked his first home run on September 12, a solo shot off Arizona’s Josh Collmenter. He collected three more hits in that game and went a perfect 4-4 with a walk, stolen base, and three runs scored.

In spite of Seager’s otherworldly .467/.568/.733 slash line and 1.301 OPS through his first nine games, Mattingly stated on September 12 that Rollins would replace Seager as the team’s starting shortstop when the veteran returned from injury. Rollins eventually did come back, but he never succeeded in ousting Seager from the starting lineup. Seager started the majority of the Dodgers’ games at short, missing only two on September 24 and 25 due to sore legs.

Mattingly’s principal concern with Seager was his defense. Rollins was a four-time gold glove winner, while Seager was a 21-year-old with no big league experience who scouts argued was simply too tall and too slow to play shortstop effectively at the major league level. Not surprisingly, Seager made his fair share of defensive mistakes. Over 21 games at shortstop, he tallied a .949 fielding percentage and committed five errors, two of which came in a single game against the Los Angeles Angels that led to one unearned run.

Seager’s prowess with the bat forced Mattingly’s hand, and the Dodgers skipper reasoned that what the youngster could contribute offensively outweighed his potential liability on defense. Seager owned a .421 weighted on-base average (wOBA) and, according to, a 1.5 wins above replacement (WAR) by season’s end. In contrast, Rollins’s wOBA sat at .283, 13.8 points below that of Seager, and his WAR was barely above replacement level at 0.2. Seager, then, was the obvious choice.

The question about Seager regarding the postseason was not if he would be on the roster – he had at very least earned a spot on the Dodgers bench and would have served as a valuable pinch hitter – but rather if he would remain as the team’s starting shortstop. When Mattingly released his lineup prior to the first game of the NLDS on October 2, observers were somewhat surprised to see Seager in the starting lineup and utterly amazed to see him batting third.

Mattingly told the Los Angeles Times that he felt the three hole was “the best spot” for Seager; high praise considering that the number three spot is usually reserved for a team’s most well-rounded hitter. For his part, Seager embraced the opportunity and felt no added pressure to perform. “That’s a meaty part of the order, so you’ve got to go out and give good [at-bats]”, he told the Times. “But other than that, there’s no extra pressure.” Mattingly reassured his shortstop that, regardless of his placement in the batting order, “It’s still a baseball game.”

Whatever Seager does (or fails to do) during the 2015 postseason, there’s little doubt that he is one of the future faces of the Dodgers organization. With Yasiel Puig the subject of recent trade rumors and his conflicts with Mattingly becoming fairly routine, Seager has the opportunity to step into a role as a leader in Los Angeles. His meteoric rise from Double-A to hitting third on the Dodgers postseason roster is a good story and epitomizes the MLB youth movement, but for Seager, it’s simply the beginning of what is likely to become a superstar career.




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