"I think he's worth every bit of it," Rasner said in a telephone interview Thursday. "He's young, he knows how to pitch already and he knows how to pitch very well. Whatever press he's getting is absolutely true. He's the real deal. He's not going to be going 24-0 in the big leagues, but I think he's definitely a high-end rotation pitcher for sure."
Tanaka, 25, went an eye-popping 24-0 with a 1.27 ERA last season for Rakuten, leading his club to a Japan Series championship. He landed in the United States this week and is being represented by Casey Close of Excel Sports Management.
The Yankees, Dodgers, Angels, Mariners and D-backs are among the most prominent suitors for the hurler's services, with bidding expected to surpass $100 million, plus a $20 million posting fee. Rasner said that if he were a general manager, he would not blink at offering that size of contract to Tanaka.
"I think he's young and you're going to get a lot of wins out of his arm," Rasner said. "I absolutely would [offer $100 million]. He was very fun as a teammate, but I became a fan of the guy watching him, what he'd do and how he'd attack hitters. I really think he's going to do well. He's going to fit into the clubhouse, he's going to work and he's going to do everything that you'd want him to do."
Rasner said he has heard people compare Tanaka to Hiroki Kuroda, but is not sure those comparisons completely click. He said Tanaka is a breed all his own, describing him as "a control pitcher who is a power pitcher when he wants to be."
"I've never seen guys be able to do what he does," Rasner said. "I think he's really special. I think his stuff is electric when he wants it to be. When he needs that little extra, it's there, and other times he knows how to move the ball, sink the ball, change speeds, mess with timing. I really think he's his own man."
Rasner said Tanaka seemed to take his game to another level in 2013, starting to change hitters' timing by quick-pitching and then using a long, slow delivery. Then, of course, there is the matter of Tanaka's lethal splitter.
"It's so nasty," Rasner said. "I think when he gets on big league mounds, I think it's going to be nastier. I don't know how guys even fouled the ball off sometimes. It looks like it starts at their waist and hits the dirt in front of the plate. I don't understand it. It's nasty. It's an absolute strikeout pitch."
Hitters will also have to watch out for an extra gear from Tanaka. Rasner said he has seen Tanaka make his velocity leap when situations dictate it, while still keeping his control.
"When he gets in trouble, he shows heart. That really comes out when he needs it to," Rasner said. "He gets nasty. He gets in trouble and he'll jump up five, six, seven, 10 miles an hour. He's not afraid of hitters and that really is what makes his competitiveness.
"He pitches at 89, 90, 91 [mph], and then he can jump up to 97, 98, 99, and locate it. It's not a fluke. When you're having to respect that split-finger, that 96 and 97 is even faster."
Rasner said a big league pitching coach will likely whittle down Tanaka's arsenal from 10 to 12 pitches to about four "plus" pitches, which is just one of the adjustments that Tanaka will be asked to make with a jump to the big leagues.
"I was really impressed with him studying English," Rasner said. "He's been studying for the last few years now. He tries his English out with the English-speaking players, and I thought it was really cool, him doing that and preparing himself for that. He's trying to fit into the clubhouse, and I thought that was great."
Rasner said he sees no reason Tanaka would be intimidated by pitching in the big leagues, not after having achieved celebrity status in his home country.
"Guys ask me if he can pitch in a big market and I say, 'Absolutely he can,'" Rasner said. "He's very professional on game day. He's very business-like. I think he'll thrive and do well. He's had all of Japan watching him for years. I hope this all does work out for him because he's really special."