Doi had spent 2009 and 2010 in the Lions bullpen. In 2009, it appears he was on the disabled list for three months. In 2010, he opened his season with 2/3 IP and 5 ER against Chiba Lotte. He followed that with a 2 ER 1 IP outing against Softbank and then spent three months without throwing a pitch. He came back in July and his first outing was a 3 ER, 2/3 IP effort against Orix. Then he went 22 outings with only three earned runs. Those 22 outings constituted 15 2/3 IP. It appears obvious that Doi was used as a LOOGY (Lefty One Out GuY) by Seibu. This contrasts to how he was used in Yokohama from 2004 - 2008 where he appears to be an oft-injured, but relatively average starting pitcher. Before then, from 1998 - 2003, he was a very effective set up man for Seibu.
Using Pitch FX, I have data from 2009 and 2010 on Doi when he pitched for the Seibu Lions. He is primarily a fastball/slider southpaw. The fastball comes in at 83 mph and has flashed as high as 88 mph. His slider is 77 mph and appears useful against left handed batters. It is really his bread and butter pitch. When forced to throw against righties, he mixes in an apparently inconsistent 76 mph change and low 80s two seamer. The two seamer sometimes shows up as a show me pitch with lefties.
Using the same method I used earlier for Yu Darvish, Tsuyoshi Wada, and Wei-Yin Chen, I predicted Doi performance in the Majors over a 50 IP run:
31 K, 21 BB, 8 HR, 5.21 FIPThat will not do in the Majors. However, it should be mentioned that Doi's 2008 year was used in the translations and that includes time spent starting for Yokohama being exposed to right handed batters. This inclusion may actually even out as he is going through what you would expect to be age related decrease in talent as well as not competitively pitching last year. His numbers look better when adjusted to AAA:
39 K, 17 BB, 6 HR, 4.25 FIPAn he appears to be above average in AA:
49 K, 14 BB, 5 HR, 3.34 FIP
Yoshihiro Doi is unlikely to provide much value to the MLB squad. He appears more as potential LOOGY depth for the Majors, but more in line to provide closer quality outings in Bowie or handed sensitive outings for Norfolk.
In others words, Doi is filler. I think he is a good kind of filler. Filler is needed in every organization. The primary purpose of it is to enable higher probability prospects to put in at bats and innings to get better. For instance, your young shortstop prospect needs to someone to catch the ball when he throws to first base. In that simple way of looking at things, that is what filler is good for. Once that level is met, there are other considerations for filler. You want a player who wants to be there and will work hard to be there. Doi fits that model. He has worked very hard at coming over to the United States and has supposedly stated that if his American tenure is relegated to the minors then so be it. He will work hard to get to the majors, but will be happy and content competing in the minors. You really do not want any malcontents if their use is primarily as filler.
Additionally, you want a player who fits in with an organizational goal. For Doi, he is part of the international expansion of the Orioles organization. Doi may specifically not be particularly promising, but the trials and tribulations he faces acclimating to the Orioles' system and to the United States in general informs the Orioles how to make the system better to help future signings. Having a personal trainer at the MLB level is fine because there is more money to throw around. However, minor league players do not have that luxury. The Orioles will need to understand how to best help international prospects succeed.
Perhaps with an eye even further on the horizon, Doi appears to be someone who is dedicated to baseball. He is a 35 year old who has suffered multiple injuries and is trying to prolong his career in the United States. I do not know his interests, but Doi may be someone who could be indoctrinated into the Orioles system and eventually be converted into someone who could help scouting lower level players in Japan, Korea, etc. This is a very peripheral objective, but I do think the more the Orioles embrace all levels of foreign players that they will be more comfortable in effectively utilizing foreign talent.
Simply put, Doi is an important signing because it shows investment in foreign-sourced players.