Tatsuya Imai To Sign With Houston Astros

In mid-November, the Seibu Lions officially posted Imai to MLB teams, opening a 45-day window for the righty to negotiate with interested parties. The Mets, Cubs, Orioles, Phillies, and Yankees were among the clubs linked to him in the past six weeks. The Astros, notably, were not.

There’s no question Houston needed another starting pitcher. After losing Framber Valdez to free agency, the Astros’ rotation was full of question marks behind ace Hunter Brown.

Cristian Javier and Lance McCullers Jr. are talented pitchers with complicated injury histories. And while the front office clearly sees something in Mike Burrows – they trade their No. 4 and No. 5 prospects to acquire him – he only has 99.1 MLB innings to his name. Neither Spencer Arrighetti nor Jason Alexander is much of a known quanitity either.

However, it was unclear how much Houston would be willing to spend this winter.

Asked about his rotation early in the offseason, Astros GM Dana Brown told reporters, “I think it’s going to be headed up with [Hunter] Brown. We’re going to have some conversations, like we’ve had in the past, with [Framber] Valdez. We’ve got some young guys. We’re going to see what they can do, and we’re going to have some other guys coming back off the IL.”

The GM never ruled out the possibility of a big free agent signing, but those don’t exactly sound like the words of someone planning to add one of the top starters on the market.

Yet, Imai didn’t end up signing for the kind of money you’d expect one of the top starters on the market to receive. His contract looks more like the deals Yusei Kikuchi and Michael Wacha signed last winter instead of the ace money many expected him to earn when the offseason began.

Before Imai was posted, ESPN’s Jeff Passan wrote about his potential market. The 12 sources he spoke to offered very different ideas about the kind of contract Imai would sign, with numbers ranging from $80 million to $200 million.

MLB Trade Rumors predicted a six-year, $150 million deal, while Ben Clemens of FanGraphs suggested five years and $100 million. Here are Just Baseball, we thought six years and $114 million (with an opt-out after year three) would get it done.

Interestingly, the median prediction of FanGraphs readers from the website’s contract crowdsourcing exercise was closer than that of any industry insiders or experts: four years and $64 million.

Needless to say, Imai’s $54 million guarantee is a lower number than any of those predictions. It’s surely less than he and agent Scott Boras were hoping for, although, in a best-case scenario, his opt-outs could help him secure more money overall than if he had signed a longer-term deal.

In 2026, Imai will look to prove that the stuff that made him an ace in NPB will indeed translate to MLB. If he succeeds, he’ll collect $21 million for his efforts and return to free agency with another opportunity to land the contract he did’t get this time around.

Meanwhile, the teams that missed out on Imai will have to look elsewhere for starting rotation upgrades. The best starters left unsigned include Valdez, Ranger Suárez, and Zac Gallen, while top trade candidates include Freddy Peralta, MacKenzie Gore, Mitch Keller, and Edward Cabrera.

To learn more about Tatsuya Imai, his arsenal, and his chances to succeed in Major League Baseball, check our Aram Leighton’s full write-up from earlier this offseason.