Earlier this week, the great NPB prospect maven, Patrick Newman, ran down a list of the 2013 NPB free agents of interest. He identifies five free agents as likely candidates for impact in the MLB:
1. RP Kyuji Fujikawa
2. SS Hiroyuki Nakajima
3. SS Takashi Toritani
4. 2B Kensuke Tanaka
5. RP Hideki Okajima (who is poised for his second tour of MLB duty)
Newman — a Japanese speaker and a far more qualified scout — offers about the best scouting and contract analysis for which one could ask. But today, let us study the coin’s tail and examine the stats of these players in context with their leagues.
NOTE: My wOBA+, FIP+ and BABIP+ calculations are league adjusted only, not park adjusted.
RP Kyuji Fujikawa
Newman calls Fujikawa, rightly, the head of the class. I have previously examined Fujikawa’s impressive numbers and prognosticated on how his numbers would transition in the MLB. My conclusion, based on his numbers, is that he could easily be a high-leverage reliever in the MLB, starting on day one:

Two of the last three seasons have not been particularly his best years, but even at his worst, Fujikawa is an excellent NPB pitcher. I think we can expect anything from 70 FIP- to 90 FIP- from him in the MLB — at least for a season or two.
SS Hiroyuki Nakajima
I have written about Nakajima on several occasions (when the Yankees paid his posting fee, when the Yankees looked like they might execute a sign-and-trade, and when he put up another great year in the NPB in 2012), and I suspect he could be a starting infielder for a good number of MLB teams.
Newman reports Nakajima’s aging range will lead to an infield job outside of shortstop, and I have little reason to doubt that. In all likelihood, he will sign as a utility player, but I think he very well could play himself into a starting job, much like Norichika Aoki did in 2012.

I am bullish on Nakajima and think he could reasonably do as Aoki did and translate much of his offensive numbers cleanly into the MLB. If not a perfect 1:1 translation, Nakijima should still have no problem hitting in the 100 wRC+ to 110 wRC+ range, which is great for a middle infielder.
SS Takashi Toritani
According to Newman, Toritani has a better hope of sticking at shortstop than Nakajima, but since his offensive production is so walk-heavy — a trait that does not bode well for (domestic) minor leaguers since walk-rates do not translate cleanly into the MLB — teams may not offer him much in the way of either playing time or remuneration. If he can bring his strong offense and decent defense to the States (or Canada), he would make for a healthy catch:

He had a particularly good 2011 season, but the 119 BABIP+ was clearly a departure from his recent norm, so I think we can consign him to a a 115ish wOBA+ in the NPB. It is hard to say exactly how those numbers would translate into the MLB, but my developing rule of thumb is to make it worse by 20 points, which would be about 95 wRC+, which is 10 wRC+ points better than the league average shortstop.
SS Kensuke Tanaka
Tanaka may be the only second baseman of the three infielders testing the MLB markets, but he grades as the best defender. Also, Newman says Tanaka is possibly willing to sign a minor league contract, which should essentially guarantee he will be in the US (or Canada) within the year. His numbers do not suggest he would make for a suitable starter in the MLB, but given his versatility and small ball skills, he could make for a quality utility player for many teams:

Tanaka profiles much like a 75 wRC+ to 95 wRC+ infielder. If his defense is as good as Newman suggests, and if he is able to hitting in the upper levels of that range, then Tanaka will have no problem competing for a bench spot — or even a starting role on a team struggling for infielders. In all likelihood, though, he is Kaz Matsui with even less offense, but more defense.
RP Hideki Okajima
Blast from the past! Okajima has finished his one-year spirit journey through the NPB and is poised for an MLB comeback. He lasted only 7 MLB games in 2011, and then the Yankees released him in February 2012, but in Japan, he dominated like an MLB veteran should. He appears well-poised to play a valuable role out of an MLB bullpen in 2013:

Okajima’s first three seasons in the MLB were exceptional. If he is healthy and feeling younger, he could again post numbers in the 80 to 90 FIP- range.
Much of these projections are optimistic. There is always a chance any one of these players could have their leg snapped within the first month and never be the same again. They might also have certain skillset that for whatever reason just does not translate into MLB parks or against MLB hitters/pitchers. But regardless of the possibilities, the relatively thin infield market and the, as always, wealthy reliever market may be richer than we might think.