Cubs' Shota Imanaga shrinks ERA to 0.84, the lowest mark through first 9 career starts in MLB history

Shota Imanaga was almost an afterthought in free agency compared to Team Japan teammates Shohei Ohtani and Yoshinobu Yamamoto, but he should definitely have all of MLB's attention now.

The Chicago Cubs left-hander threw seven shutout innings against the Pittsburgh Pirates on Saturday, lowering his ERA from 0.96 to 0.84. That mark not only leads MLB but also is the lowest ERA ever posted by a pitcher (excluding openers) in his first nine career starts in league history.

MLB.com's Sarah Langs notes the only other pitcher to come in below 1.00 was Fernando Valenzuela, who went on to win the 1981 Cy Young Award for the Los Angeles Dodgers in the season widely remembered as "Fernandomania."

Among all pitchers to start in any given season, Imanaga's ERA ranks around the likes of prime Walter Johnson, Jacob deGrom and Zack Greinke.

For seven innings Saturday, Imanaga kept the Pirates off-balance with a pitch mix composed almost entirely of four-seam fastballs and splitters, with four curveballs mixed in. He struck out seven, walked one and allowed only four hits, all singles, in a 1-0 Cubs win.

Imanaga has been turning heads since his debut and now looks like the biggest bargain of the offseason.

Shota Imanaga already looks like an ace

The Cubs landed Imanaga on a very manageable four-year, $53 million deal, which the Cubs can turn into a five-year, $80 million deal after the second season. They will almost certainly be doing that. The deal is a fraction of the $700 million Ohtani got and the $325 million Yamamoto received, both from the Dodgers, though those two players are also absolutely living up to their contracts.

They just aren't blowing away every expectation and precedent like Imanaga.

There were indications that Imanaga was a star in the making well before he put pen to paper with the Cubs. When Team Japan needed a starter for the 2023 World Baseball Classic championship, it turned to Imanaga despite Ohtani and Yu Darvish being available. He allowed four hits and one run in two innings of work against a stacked Team USA lineup, but the bigger news was what Statcast picked up.

Imanaga had the best Stuff+ of the tournament, which included Ohtani, Yamamoto and 2022 NL Cy Young winner Sandy Alcantara. He was good while playing in Japan, with a 2.66 ERA and a strikeout title for the Yokohama BayStars last season, but that WBC appearance should've left MLB teams little doubt that Imanaga's arsenal could survive stateside.

He has obviously done more than survive. His high-spin, low-90s fastball has been the best four-seamer in MLB by pitch value, with batters hitting .184 against it entering Saturday. His stuff has been lifted by a command and poise rarely seen from pitchers facing major leaguers for the first time.

Granted, Imanaga likely has some regression ahead of him; ERA predictors FIP, xFIP, SIERA and xERA all have him pegged between 2.19 and 3.09. But that's still a level that makes the $53 million price laughable for a rising NL Central contender.