MLB ERA leaders: How Cubs pitcher Shota Imanaga is in line for historic rookie season

The offseason featured the signing of several high-profile pitchers from Asia. None were more widely sought after than Yoshinobu Yamamoto.

The Dodgers signed the three-time Eiji Sawamura Award winner to a massive 12-year, $325 million contract, the largest total contract ever signed to an MLB pitcher, let alone one who had never thrown a pitch in the big leagues. He was 25 years old. He was highly accomplished. He was expected to be the star of the international class.

Yamamoto has lived up to expectations, which is what makes it all the more surprising that he has not been the best international signing to date. That honor belongs to Cubs southpaw Shota Imanaga. 

Imanaga doesn't feature the Nippon Baseball League accolades of Yamamoto. He's five years older than his fellow countryman. He averages three miles per hour less on his fastball. And yet, Imanaga has been off to not just a standout start to his MLB career; he's off to a historic one.

Sporting News takes a look at Imanaga's start to the season, and what it would take for it to officially reach the record books.

MLB ERA leaders

Imanaga leads the majors with a 0.84 ERA through his first nine starts of the season. He has a comfortable advantage over the rest of the league, though there are several starters with ERAs below 2.00.

Here's a look at the qualifying ERA leaders in 2024:

Shota Imanaga scouting report

Part of what makes Imanaga such an intriguing pitcher is that he does not throw as hard as most do in today's game. Baseball Savant places his fastball velocity in the 18th percentile of the league.

However, that doesn't mean the numbers don't favor the southpaw. He ranks in the 92nd percentile in expected ERA, 96th percentile in chase rate, 86th percentile in whiff rate, 79th percentile in strikeout rate and 90th percentile in walk rate. His fastball is the best in fastball run value and his pitching run value is also the best overall.

Imanaga features a diverse array of pitches which helps to keep batters off balance. Beyond the four-seamer, which is his most used pitch at 58.2 percent, Imanaga has also thrown a splitter, sweeper, curveball, sinker and changeup.

The splitter is his second-most used pitch at 31.8 percent and features a run value of three. The offering has 32.5 inches of vertical break and 11.2 inches of horizontal break.

No other pitch has been used more than 6.3 percent, the top offering being that sweeper. It has 9.6 inches of horizontal break and 36.2 inches of vertical drop, both below average in movement. It has more of a curveball break, though his curveball, thrown 3.2 percent of the time, has 65.8 inches of vertical drop and 9.4 inches of horizontal break.

He's only thrown the sinker three times and the changeup once, and neither pitch has been put in play. 

Soft-tossing pitchers are most often associated as groundball pitchers, but that has not been the case for Imanaga. His groundball rate is only in the 39th percentile at 40.1 percent. His flyball rate of 39.2 percent rates as the sixth-highest in baseball, though his line drive rate is the third-lowest, per Baseball Savant.

Imanaga rates in the 60th percentile in both average exit velocity and barrel rate, indicating he's been above average at limiting explosive contact this season.

By all accounts what Imanaga has done so far appears sustainable, even if it is not in line with most pitchers who feature triple-digit heaters.

Shota Imanaga stats

Imanaga has begun the 2024 season with a minuscule 0.84 ERA and 2.20 FIP (fielding independent pitching) through the first nine starts of the season. In 53.2 innings, he has struck out 58 batters, walked only nine, given up only 40 hits and just three home runs.

In the modern era, which dates back to 1920, that 0.84 ERA is the lowest for any starting pitcher through their first nine career starts, according to Stathead. The previous record had been 1973 Expos rookie Steve Rogers, who had a 1.20 ERA through his first nine starts. In 2023, Marlins rookie Eury Perez posted a 1.34 ERA in his first nine starts, which ranks third.

Rogers went on to finish the season with a 1.54 ERA in 17 starts and finished second in Rookie of the Year voting. Giants outfielder Gary Matthews won the honors after slashing .300/.367/.444 in 148 games with 12 homers and 17 steals. Perez pitched 19 starts and had a 3.15 ERA with 108 strikeouts in 91.1 innings and finished seventh in Rookie of the Year voting. 

Best ERAs in MLB history

Imanaga is currently in line to have the lowest ERA by a starting pitcher in the modern era based on how he has begun the season. But if he can actually set the record, it would take perhaps the best pitching season in MLB history.

In 1968, Cardinals ace Bob Gibson set the record for the lowest ERA by a starter in modern MLB history with a 1.12 mark in 304.2 innings of work. He won the NL Cy Young and MVP. He also struck out 268 batters and threw 28 complete games (with 13 shutouts).

Here's a look at the 20 lowest ERAs in MLB history among qualifying starting pitchers in the modern era: