Worst Single-Season ERAs in MLB History

From Les Sweetland's 7.71 nightmare to Jose Lima's collapse - the pitching seasons nobody wants to remember

Every pitcher dreams of posting a sub-2.00 ERA and dominating the league. But some pitchers live the opposite nightmare.

Les Sweetland went 7-15 with a 7.71 ERA in 1930. Jim Deshaies allowed 30 home runs and posted a 7.39 ERA in 1994. Jose Lima's career collapsed with a 6.99 ERA in 2005.

These are the worst single-season ERAs in MLB history — the records nobody wants, the seasons that ended careers, and the numbers that still make pitching coaches cringe.

The All-Time Worst: Les Sweetland, 1930

7.71 ERA | 7-15 Record | 167.0 IP | Philadelphia Phillies

Les Sweetland holds a record that's stood for 96 years and will probably never be broken: the highest ERA ever by a qualified pitcher in modern baseball history.

In 1930, Sweetland allowed 288 hits in just 167 innings. He gave up 143 earned runs — nearly one per inning pitched. Opposing batters hit .373 against him.

The 1930 Disaster

Sweetland didn't fail alone. The entire 1930 Philadelphia Phillies pitching staff was historically awful:

  • Team ERA: 6.71 (worst in modern MLB history)
  • Runs allowed: 1,199 (7.69 per game)
  • Record: 52-102
  • Only Phil Collins (4.78 ERA) and Ray Benge (5.70 ERA) were remotely competent

The Phillies scored over 6 runs per game as a team and still finished last. Their opponents set an all-time record for runs scored against a single team.

Why Was 1930 So Bad?

The 1930 season became known as "The Year of the Hitter." A livelier ball caused offensive numbers to explode across baseball:

  • The National League hit .303 as a whole
  • The Phillies hit .315 as a team (and still lost 102 games)
  • They played in Baker Bowl — a bandbox where right field was 280 feet from home plate
  • League-wide ERA averaged 4.97

But even in this offensive era, Sweetland's 7.71 ERA stood out as brutally bad. He was 54% worse than league average.

Opening Day Deception

The most misleading part of Sweetland's 1930 season? He threw a three-hit shutout on Opening Day against Brooklyn. The Phillies won 1-0. Sweetland never approached that level of performance again all season.

Top 10 Worst Single-Season ERAs (Qualified Pitchers)

Rank Pitcher Year ERA Record Team
1 Les Sweetland 1930 7.71 7-15 Phillies
2 Jim Deshaies 1994 7.39 6-12 Twins
3 Jack Knott 1936 7.29 9-17 Browns
4 Claude Willoughby 1930 7.59 4-17 Phillies
5 Sloppy Thurston 1933 7.18 5-18 Dodgers
6 Bump Hadley 1932 7.15 4-11 Browns
7 Bill Swift 1939 7.04 1-8 Pirates
8 Jose Lima 2005 6.99 5-16 Royals
9 Les Munns 1936 6.94 3-14 Dodgers
10 Wayne LaMaster 1938 6.77 8-18 Phillies

Notice a pattern? Most of these disasters happened in the 1930s, baseball's highest-scoring decade. But a few modern pitchers managed to join this infamous list.

Modern Era Disaster: Jim Deshaies, 1994

7.39 ERA | 6-12 Record | 130.0 IP | Minnesota Twins

Jim Deshaies had been a solid pitcher for years. He posted a 3.25 ERA as a rookie in 1986. He set the modern record with eight consecutive strikeouts to start a game in 1986.

But in 1994, everything fell apart.

The Collapse

Deshaies' 1994 season was brutal:

  • Allowed 30 home runs in just 130 innings (one every 4.3 innings)
  • Gave up 219 hits
  • Struck out only 80 batters
  • Had the highest ERA for any pitcher with 30+ starts since 1930

The Twins released him after the season. He pitched two more games with the Phillies in 1995 before retiring at age 35.

What Went Wrong?

Deshaies never had overpowering stuff. He survived on control and changing speeds. But by 1994, shoulder problems had sapped what little velocity he had.

As Deshaies himself said: "I have three pitches from one angle and who knows what they're going to do?"

When those three pitches became hittable, batters destroyed him.

The Tragic End: Jose Lima, 2005

6.99 ERA | 5-16 Record | 168.2 IP | Kansas City Royals

Jose Lima's career arc is one of baseball's saddest stories. From dominance to disaster in just five years.

Lima's Peak

In 1999, Lima went 21-10 with a 3.58 ERA for the Houston Astros. He was an All-Star. Fans loved his charismatic "Lima Time" celebrations.

Then the Astros moved from the Astrodome to Minute Maid Park in 2000. The new park's shorter dimensions exposed Lima's flyball tendencies. His ERA ballooned to 6.65.

The 2005 Nightmare

By 2005, Lima was 33 and pitching for Kansas City. His season was a disaster:

  • 6.99 ERA (62 ERA+, meaning he was 38% worse than league average)
  • Allowed 219 hits in 168.2 innings
  • Gave up 31 home runs
  • Posted a 1.660 WHIP

Lima pitched four more games in 2006 with a 9.87 ERA before his career ended. He died suddenly in 2010 at age 37.

Why These ERAs Happened

Looking at the worst ERA seasons in history reveals a few common patterns:

1. High-Offense Eras

Most of these disasters happened in 1930-1940 or 1994-present — baseball's two highest-scoring eras. When offense surges, struggling pitchers get exposed.

2. Teams Let Them Keep Pitching

Modern teams would never let a pitcher accumulate 150+ innings with a 7.00+ ERA. But in the 1930s, teams had smaller rosters and fewer bullpen options. Starters had to eat innings no matter how bad they were.

3. Bandbox Ballparks

Many of these disasters happened in hitter-friendly parks:

  • Les Sweetland pitched in Baker Bowl (280 feet to right field)
  • Jose Lima struggled when Houston moved to Minute Maid Park
  • Jack Knott pitched for the Browns in Sportsman's Park

4. Lost Velocity or Control

Most modern pitchers on this list were dealing with injuries. When velocity drops or control vanishes, hitters feast.

The Worst ERA+ Seasons

ERA+ adjusts for park and league factors. A score of 100 is average. Below 100 is below average. Here are the worst ERA+ seasons ever:

Pitcher Year ERA+ ERA Context
Jose Lima 2005 62 6.99 38% worse than league average
Les Sweetland 1930 71 7.71 29% worse than league average
Jim Deshaies 1994 65 7.39 35% worse than league average

Even accounting for offensive environment, these seasons were historically bad.

Honorable Mentions: Bad But Not Qualified

Some pitchers had ERAs worse than 7.71 but didn't pitch enough innings to qualify for the ERA title:

  • Les Munns (1934): 13.14 ERA in 12.1 innings
  • Bill Kissinger (1898): 10.50 ERA in 18 innings
  • Numerous relief pitchers have posted ERAs above 10.00 in limited innings

The qualification threshold (1 inning per team game, or 162 innings for a modern season) prevents these small-sample disasters from claiming the "worst ever" title.

Could This Happen Today?

Could a modern pitcher post a 7.71 ERA in a full season? Probably not.

Why Modern Pitchers Won't Break This Record

Several factors prevent modern disasters of Sweetland's magnitude:

1. Quicker Hooks
Teams pull struggling pitchers immediately. Nobody gets 167 innings to post a 7.71 ERA.

2. Better Player Development
Modern pitchers with ERAs above 5.00 get sent to the minors or released. They don't keep getting starts.

3. Deeper Rosters
Teams have 13-man pitching staffs. They don't need to keep running out struggling starters.

4. Advanced Analytics
Teams identify struggling pitchers faster using metrics like FIP, hard-hit rate, and exit velocity.

5. Lower Scoring Environment
Despite recent offensive increases, baseball isn't close to 1930 scoring levels.

The Last Qualified 6.00+ ERA

Jose Lima's 6.99 ERA in 2005 was the last time a qualified pitcher posted an ERA above 6.00. That was 21 years ago. The modern game simply won't allow disasters like Sweetland's 1930 season.

Lessons from the Worst

What can we learn from these disasters?

1. Context Matters

A 5.00 ERA in 1930 was actually decent (103 ERA+). The same 5.00 ERA in 1968 would be historically terrible (roughly 50 ERA+).

Always adjust for era when judging pitchers.

2. One Bad Season Doesn't Define a Career

Jim Deshaies had a solid career despite his 1994 disaster. He pitched 12 years in the majors and is now a respected broadcaster.

Les Sweetland pitched well in 1929 (13-11, 5.11 ERA) before his 1930 collapse.

3. Environment Matters

Park factors, ball liveliness, and offensive levels all impact ERA. Put the wrong pitcher in the wrong situation, and disasters happen.

4. Decline Can Be Sudden

Jose Lima went from All-Star (1999) to finished (2005) in six years. Velocity loss and loss of command can end careers quickly.

The Phillies' 1930 Legacy

The 1930 Phillies remain the worst pitching staff in modern baseball history:

  • 6.71 team ERA (record)
  • 1,199 runs allowed (record)
  • Two qualified pitchers with ERAs above 7.00 (Sweetland 7.71, Willoughby 7.59)
  • 52-102 record despite scoring 944 runs (6.06 per game)

That season forced MLB to deaden the baseball for 1931. Scoring dropped immediately.

Final Thoughts

Les Sweetland's 7.71 ERA has stood as the worst qualified ERA for 96 years. It's a record that will probably never be broken.

Modern baseball simply won't allow a pitcher to post 167 innings with an ERA that high. Teams pull struggling pitchers too quickly. Player development is too advanced. Analytics identify problems too fast.

But these disasters remind us how hard pitching is. Even major league pitchers can have seasons where nothing works. When velocity drops, control vanishes, or the ball gets too lively, ERAs can explode.

These are the cautionary tales — the pitchers who had the opposite of a Cy Young season. The ones who set records nobody wants.

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