Jacob deGrom has earned a reputation as one of the most electrifying and dominant pitchers in Major League Baseball history. Since his debut in 2014, the right-handed flamethrower has posted statistics that frequently defy modern offensive trends, drawing comparisons to the all-time greats. Central to any evaluation of his career is his earned run average (ERA), a foundational metric that, when examined against league averages, reveals the true magnitude of his dominance. This article provides a detailed comparative analysis of Jacob deGrom’s career ERA alongside the shifting league norms during his tenure, unpacking the context, the outliers, and the legacy he has built along the way.

Understanding ERA and Its Significance

ERA, or earned run average, measures the average number of earned runs a pitcher allows per nine innings pitched. The formula is straightforward: (Earned Runs × 9) ÷ Innings Pitched. A lower ERA signals better performance because it means the pitcher is preventing opponents from scoring. However, ERA is not a perfect stat—it can be influenced by ballpark factors, defense behind the pitcher, and the quality of opposing lineups. Nevertheless, when contextualized against the league average for a given season, ERA offers a powerful snapshot of a pitcher’s effectiveness relative to their peers.

Over the decades, league-average ERA has fluctuated significantly. In the so-called “dead ball” era of the early 1900s, averages were below 3.00. During the “steroid era” of the late 1990s and early 2000s, they ballooned past 4.50. In deGrom’s career span (2014–2024), the National League average ERA has typically hovered between 4.00 and 4.50, with occasional dips due to changes in the baseball itself or the adoption of defensive shifts. Understanding these swings is essential to appreciating just how far deGrom has stood above the crowd.

Jacob deGrom’s Career ERA: A Season-by-Season Breakdown

DeGrom made his MLB debut with the New York Mets on May 15, 2014. Over the next decade, he compiled a career ERA of approximately 2.52 (as of the end of the 2023 season), a figure that ranks among the best in the live-ball era for any pitcher with at least 1,300 innings. The following table outlines his ERA in each full season (minimum 80 innings pitched) alongside the corresponding National League average ERA.

SeasondeGrom ERANL Average ERADifference
20142.693.72-1.03
20152.543.78-1.24
20163.044.01-0.97
20173.534.28-0.75
20181.704.01-2.31
20192.434.51-2.08
20202.384.75-2.37
20211.084.16-3.08
20223.083.96-0.88
20232.674.31-1.64

Source: Baseball Reference and FanGraphs (league averages compiled from season data).

The numbers tell a story of three distinct phases: an early career of solid-to-excellent performance, a peak of historically unprecedented dominance (2018–2021), and a late-career rebound marred by injuries. The 2021 season stands out as perhaps the greatest pitching season in modern history—deGrom posted a 1.08 ERA over 92 innings before missing the second half with injuries. That mark is more than three full runs better than the league average, a gap rarely seen since the mound was lowered in 1969.

Peak Seasons in Focus: 2018 and 2021

In 2018, deGrom recorded a 1.70 ERA while pitching for a Mets team that finished 77-85. He won the National League Cy Young Award unanimously, despite a mediocre win-loss record of 10-9. That season, his ERA+ (ERA adjusted for park and league factors) was 218, meaning he was 118% better than the average pitcher. The league average ERA was 4.01—his ERA was nearly 2.5 runs lower.

The 2021 campaign, though shortened to 92 innings, was even more absurd. DeGrom’s strikeout rate (45.1% of batters faced) and walk rate (5.5%) created a K-BB% of 39.6%, the highest ever recorded (minimum 50 IP). His 1.08 ERA was buoyed by a .141 opponents’ batting average. The National League averaged 4.16 runs per nine innings that year, making deGrom’s dominance a historical outlier. For context, no qualified starter since Pedro Martínez in 2000 had posted an ERA below 1.20.

To appreciate deGrom’s comparative edge, one must understand the offensive environment of each era. From 2014 to 2023, the NL average ERA fluctuated between a low of 3.72 (2014) and a high of 4.75 (2020). Several factors drove these changes:

  • Juiced ball (2016–2019): Home run rates spiked, inflating ERAs across the league. The league average ERA in the NL rose from 4.01 in 2016 to 4.51 in 2019.
  • Pandemic season (2020): The shortened 60-game schedule saw unusual offensive spikes due to lack of spring training and expanded playoffs, pushing the NL average ERA to 4.75.
  • Deadened ball and shift restrictions (2022–): MLB introduced a slightly deadened baseball in 2021 (already showing effect in 2020) and, beginning in 2023, banned defensive shifts and enlarged bases. These changes brought league ERAs down slightly, averaging around 4.16 in 2021 and 3.96 in 2022 before rising again in 2023.

Throughout these fluctuations, deGrom’s ERA consistently remained well below the league norm. In every season except his worst (2017, when he pitched through injury), his ERA was at least 0.75 runs better than the league average. In his peak years, the gap exceeded 2.00 runs—a feat matched only by a handful of pitchers in history.

Comparative Analysis: deGrom vs. League Average and His Peers

ERA+ Adjustment

To standardize comparisons across different run-scoring environments, statisticians use ERA+, which adjusts ERA for ballpark and league, then normalizes to 100 (average). DeGrom’s career ERA+ of 142 means he has been 42% better than the average pitcher across his career. For comparison:

  • Clayton Kershaw (2008–2023): ERA+ 157
  • Max Scherzer (2008–2023): ERA+ 133
  • Justin Verlander (2005–2023): ERA+ 127
  • Sandy Koufax (1955–1966): ERA+ 131
  • Pedro Martínez (1992–2009): ERA+ 154

While Kershaw edges deGrom by a few points over a longer career, deGrom’s peak ERA+ from 2018–2021 is utterly unmatched. In 2021, his ERA+ was 380—meaning he was 280% better than the average pitcher that season. No qualified starter in history had ever posted an ERA+ above 300 before (Pedro’s 2000 ERA+ was 291).

Contrast with League Averages by Season

The table above makes the contrast stark. In 2018, while the league average was 4.01, deGrom allowed just 1.70 ER per 9. That gap of 2.31 runs was the largest in the majors since Dwight Gooden’s 1.53 ERA in 1985 (when the NL average was 3.88). In 2021, deGrom’s gap of 3.08 runs was even larger—an absurdity that essentially made him two entirely separate tiers of talent.

When we consider the cumulative effect, deGrom saved his teams an enormous number of runs. From 2014 to 2023, if he had pitched exactly to the league average each season, he would have allowed approximately 328 more earned runs than his actual total of 296 (over 1,055 innings). That run prevention translates directly to wins—WAR calculations suggest deGrom was worth 44.2 wins above replacement (per Baseball Reference), making him one of the most valuable pitchers in the game despite missing significant time due to injuries.

Impact on Team Success and Legacy

Team Wins While deGrom Was on the Mound

DeGrom’s brilliance did not always translate to team victories. In 2018, the Mets went just 77-85 overall, but they were 15-13 in his starts—a .536 winning percentage that, had it held all season, would have put them in playoff contention. This underscores a often-overlooked point: a dominant starting pitcher can keep a mediocre team competitive, especially when the offense gives him even modest run support.

When the Mets did reach the postseason, deGrom was their ace. In the 2015 World Series run, he posted a 2.88 ERA over four starts, including a stellar 7-inning, 2-run outing in Game 3. In 2022, his return from injury helped the Mets win 101 games, though an early playoff exit left his legacy unfulfilled in October. Still, his career postseason ERA of 2.43 (over 33 innings) shows he performed when it mattered most.

Injuries and What Might Have Been

No discussion of deGrom’s career is complete without acknowledging the injury toll that limited him to just 132 starts over his first 10 seasons (an average of 15 per year since 2015). Elbow and shoulder problems cost him the second half of 2021, most of 2022, and large chunks of 2023. Even so, his raw numbers remain staggering. A full, healthy deGrom over a 200-inning season likely would have produced an ERA in the 1.50–1.80 range, further widening the gap with league averages.

His decision to sign with the Texas Rangers in December 2022 for a five-year, $185 million contract sparked debate about whether an injury-prone pitcher could still be elite. In his first season in Texas (2023), he delivered a 2.67 ERA over 30.1 innings before succumbing to elbow surgery—a reminder of both his brilliance and his fragility.

Historical Context: Where Does deGrom Rank?

Comparing deGrom to the all-time greats requires careful adjustment for era. The league-average ERA in 1915 was around 3.00; today it’s 4.30. Using ERA+ accounts for that shift. DeGrom’s career 142 ERA+ places him tied for 19th all-time (minimum 1,000 innings) among pitchers with at least 1,000 innings, alongside names like Greg Maddux (142), Pedro Martínez (154), and Clayton Kershaw (157).

But peak performance is where deGrom truly shines. His four-year peak (2018–2021) produced an ERA of 1.85 over 546 innings, with an ERA+ of 222. That is the highest four-year ERA+ for any pitcher with 500+ innings since the mound was lowered, surpassing even Sandy Koufax (1962–1965: ERA+ 196) and Pedro Martínez (1997–2000: ERA+ 213). The only pitchers in the modern era who can claim comparable peaks are Jacob deGrom himself, Walter Johnson, and Lefty Grove—legends of the game.

What the Numbers Don’t Show

ERA and league comparisons are vital, but they don’t capture deGrom’s sheer intimidation factor. His fastball consistently sits at 98–101 mph, complemented by a devastating slider and changeup. Hitters often looked helpless, swinging through pitches that seemed to defy physics. In 2021, he struck out 45.1% of batters—a rate that crushed the previous record (Pedro Martínez, 39.3% in 1999). No pitcher had ever dominated with such a combination of power and precision.

Conclusion

Jacob deGrom’s career ERA, viewed through the lens of league averages, reveals a performer who operated on a plane far above his contemporaries. From his early years to his breathtaking peak and injury-marred later seasons, he consistently held opponents to run totals that were historically low relative to the league. The gap between deGrom and the average pitcher—often exceeding two runs per nine innings—places him in a category with the all-time greats, even if his career lacks the counting statistics that longevity typically provides.

For fans and analysts, deGrom’s career will be remembered as a study in what could have been and what was: a pitcher whose talent was so immense that he made even the best hitters of his generation look overmatched. The ERA comparisons are not just numbers—they are a testament to a rare kind of greatness, one that will be studied and debated for decades to come.

Further Reading: Explore deGrom’s complete statistics on Baseball Reference or track his season-by-season ERA+ at FanGraphs. For league average ERA trends, consult NL league pages.