Keys for Japanese players in MLB

Will Hiroyuki Nakajima, right, follow in the footsteps of Norichika Aoki, left, and Yu Darvish, center? Gary A. Vasquez/US Presswire

In November of 2010, the Minnesota Twins bid $5 million for the privilege of negotiating with Japanese infielder Tsuyoshi Nishioka, who had been posted by his NPB team, the Chiba Lotte Marines. The 26-year-old was coming off a season in which he'd hit .346/.423/.482 (BA/OBP/SLG), leading Japan's Pacific League in batting average, hits, runs and total bases.

Nishioka had won three Japanese Gold Gloves, and the Twins, whose astute scouting had led them to six division titles in the previous 10 seasons, envisioned him as their starting shortstop. After winning the bidding, they spent an additional $9 million to lock up Nishioka for the next three seasons.

Last December, the Milwaukee Brewers submitted a winning bid of $2.5 million -- half of what the Twins had bid for Nishioka -- to negotiate with Yakult Swallows outfielder Norichika Aoki. It took $2.5 million more to secure his services for the next two seasons. The 29-year-old Aoki had posted a much more modest .292/.358/.360 line with just four home runs in his final Japanese season.

Compare the two players' posting fees, contracts and prior-season statistics, and you'd conclude that Nishioka was clearly the superior player. But we know what happened next. Nishioka flopped, hitting just .215/.267/.236 in 71 games and 254 plate appearances in the majors across two seasons and spending most of the second year in Triple-A (where he continued to hit poorly). His .021 isolated power (SLG-AVG) for the Twins was the lowest of any hitter with at least 250 career plate appearances since World War II. Mercifully, he decided to return to Japan rather than stay in Minnesota for another season, taking the Twins off the hook for the third year.

Aoki, on the other hand, was a surprise success, boasting the best offensive season of any Japanese rookie since Ichiro Suzuki. He hit .288/.355/.433 with 10 homers and 30 steals, ranking fourth among NL rookies with 2.5 WARP and finishing fifth in the NL Rookie of the Year voting. He was also the first Japanese position player to see his home run total rise in his first season stateside.

Nishioka was coming off a BABIP-based career year, while Aoki had just completed his worst-ever effort, so perhaps it shouldn't have come as a shock that both players weren't quite what their most recent seasons suggested. Still, even well-informed analysts felt that Nishioka could help a team like the Twins.

His struggles, and those of other disappointing imports who preceded him, have taught major league teams that NPB stardom doesn't always translate into MLB success. However, the tantalizing talent on display in Japan motivates major league clubs to separate the players whose skill sets are well-suited to the majors from those who would be hard-pressed to sustain their success in the U.S.

One of the top NPB players angling for a move to the majors this winter is Seibu Lions infielder Hiroyuki Nakajima, whom the Arizona Diamondbacks reportedly see as a potential solution at shortstop.