Lowest career ERA in wins since 1920 (min. 50 GS):

1.11 Jacob deGrom
1.31 Dean Chance
1.32 Clayton Kershaw
1.34 Sandy Koufax
1.38 George Brunet
1.41 Andy Messersmith
1.43 Sam McDowell
1.44 Bob Veale
1.45 Nolan Ryan
1.48 Don Drysdale
1.49 Bob Knepper

Lowest career ERA during day games since 1913 (min.300 IP)

1.85 Jacob deGrom
2.45 Clayton Kershaw
2.48 Mariano Rivera
2.59 Hoyt Wilhelm
2.60 Pedro Martinez
2.63 Andy Messersmith
2.67 Gary Lavelle
2.72 Johan Santana
2.73 Joe Nathan
2.77 Bob Gibson

8 pitchers in Major League Baseball history have held hitters under a .600 OPS with runners in scoring position (200 IP min.):

Billy Wagner .548
Clayton Kershaw .578
Pedro Martinez .583
Herb Score .588
Jacob deGrom .594
Yu Darvish .597
Jim Palmer .597
Mariano Rivera .599

Only one pitcher in Major League Baseball history has held hitters to an OPS lower than .500 against pitches 101+ (90 game minimum):

Jacob deGrom .489 OPS

Best ERA since 1920 for combined 30 and 31 year-old seasons:

1.97 Carl Hubbell
2.05 Jacob deGrom
2.16 Zack Greinke
2.27 Juan Marichal
2.27 Lefty Grove
2.38 Bucky Walters
2.41 Mort Cooper
2.47 Greg Maddux
2.47 Don Drysdale
2.48 Tom Seaver
2.51 John Tudor
2.62 Kevin Brown

Here is where Jacob deGrom ranks among Major League starters since his debut on 5/15/2014:

2nd - 2.62 ERA
2nd - 2.78 FIP
2nd - 0.8 HR/9
T/5th - 10.3 K/9
T/6th - 1.05 WHIP
T/6th - 4.7 K/BB
T/6th - .221 AVG

Pitchers in Major League history with at least 7.0 WAR, 250 Strikeouts, 150 ERA+ and less than 2.0 BB/9 in back-to-back seasons:

Pedro Martinez
Jacob deGrom
Old Hoss Radbourn

Lowest ERA in no decisions over last 20 years for a single season:

0.99 Roger Clemens 2005
1.38 Jeff Samardzija 2014
1.38 Clayton Kershaw 2009
1.62 Jacob deGrom 2018
1.67 Julio Teheran 2019
1.70 Jacob deGrom 2019
1.76 Pedro Martinez 2003
1.88 Felix Hernandez 2014

Lowest ERA in losses since 1970 during a single season:

2.71 Jacob deGrom 2018

Second lowest was 2.86 by Andy Hassler in 1974