What Defines an Ace in Modern Baseball? An In-Depth Analysis
Baseball fans, who grew up admiring pitchers with 20 wins, know that the expectations for a starter in 2025 are very different from those of a decade ago, and even more distant from those of 20, 30, or 40 years ago. The complete game, as such, is almost extinct. Pitching limits have been reduced, and starters get more rest days between their outings.
In 1985, Dwight Gooden, at 20 years old, had an impressive season with a 24-4 record and a 1.53 ERA, leading the National League in complete games and strikeouts. How do today’s aces compare to those of that era?
In 2025, Paul Skenes and Tarik Skubal emerge as the star pitchers, but the evolution of the game is evident. Skenes, a National League Cy Young candidate, leads MLB with an ERA of 2.03 and tops the National League in strikeouts and WAR, but his win-loss record is only 10-10. Skubal, for his part, is the favorite to win the American League Cy Young for the second consecutive year, with only 13 wins.
The longevity of starting pitchers has changed drastically. In 1985, John Tudor achieved 10 shutouts in a single season. In contrast, in 2025, there have only been 12 shutouts in the entire league. Max Fried, with 17 wins, could be the only one to reach 20, something that was previously a requirement to win the Cy Young.
Despite statistical differences, Skenes and Skubal are having great seasons in the context of the current game, where pitcher management is different. We analyzed the performance of aces in 1975, 1985, 1995, 2005, and 2015.Analysis of Eras: What Made an Ace?
For this analysis, 12 aces per season were selected, based on WAR, innings pitched, effectiveness, and ERA+.1975
Aces: Jim Palmer, Catfish Hunter, Tom Seaver, Jim Kaat, Randy Jones, Frank Tanana, Andy Messersmith, Bert Blyleven, Steve Busby, Gaylord Perry, Jerry Reuss, Vida Blue.Ace’s Average: 20-12, 2.69 ERA, 288 IP, 244 H, 191 SO, 80 BB, 37 GS, 19 CG, 5 SHO, 138 ERA+, 6.8 WAR.MLB Starter Average: 3.80 ERA, 4.9 SO/9, 1.49 SO/BB ratio.What defined an ace in 1975?: Durability and victories.Key statistic: The aces completed 51% of their starts and averaged 7.8 innings per game.
The 1970s were rich in pitchers. Starters had heavy workloads, and the expectation was that they would finish the game. Gaylord Perry exemplified this perfectly, averaging 321 innings per season and completing 64% of his starts.
The 1975 Cy Young winners were Palmer and Seaver, who, like all Cy Young winners in the decade except Seaver in 1973 and three relievers, won 20 games. Wins were often the deciding factor in voting.1985
Aces: Dwight Gooden, John Tudor, Bret Saberhagen, Dave Stieb, Charlie Leibrandt, Bert Blyleven, Rick Reuschel, Orel Hershiser, Fernando Valenzuela, Jack Morris, Ron Guidry, Bob Welch.Ace’s Average: 18-8, 2.54 ERA, 248 IP, 204 H, 67 BB, 167 SO, 33 GS, 12 CG, 4 SHO, 157 ERA+, 6.6 WAR.MLB Starting Pitcher Average: 3.96 ERA, 5.2 SO/9, 1.65 SO/BB ratio.What defined an ace in 1985?: A great secondary pitch.Key statistic: The ERA+ of 157 was a large increase from 1975.
Gooden’s 1985 season is one of the best of all time. Saberhagen won the American League award. Gooden and Saberhagen had impressive fastballs, but this group stood out for a remarkable secondary pitch as their best weapon.
In 1985, the power game increased. The transformation from four-man to five-man rotations and the arrival of the modern closer led to fewer innings and complete games, although aces averaged nearly 250 innings.1995
Aces: Greg Maddux, Randy Johnson, David Cone, Mike Mussina, Kenny Rogers, Dennis Martinez, David Wells, Tim Wakefield, Tom Glavine, Hideo Nomo, Kevin Brown, John Smoltz.Ace’s Average: 16-7, 2.99 ERA, 202 IP, 170 H, 61 BB, 166 SO, 29 GS, 5 CG, 2 SHO, 157 ERA+, 5.9 WAR.MLB Starting Pitcher Average: 4.53 ERA, 6.0 SO/9, 1.82 SO/BB ratio.What defined an ace in 1995?: Surviving the PED era and the offensive increase.Key statistic: Increase in strikeouts per nine innings.
This was a strike-shortened season. Elite pitchers became even more dominant due to PED use and a livelier ball. Maddux and Johnson won the Cy Young, dominating in a high-offense era.
The average runs per game increased, contributing to the decrease in innings pitched and the evolution of the modern bullpen.2005
Aces: Roger Clemens, Dontrelle Willis, Johan Santana, Pedro Martinez, Andy Pettitte, Roy Oswalt, Randy Johnson, Chris Carpenter, Roy Halladay, John Smoltz, Mark Buehrle, Jake Peavy.Ace’s Average: 16-8, 2.82 ERA, 220 IP, 190 H, 46 BB, 185 SO, 32 GS, 4 CG, 2 SHO, 155 ERA+, 6.1 WAR.MLB Starting Pitcher Average: 4.36 ERA, 6.0 SO/9, 2.08 SO/BB ratio.What defined an ace in 2005?: Strike out more batters than walked.Key statistic: The strikeout/walk ratio.
In 2005, the offensive declined slightly. The aces maintained a similar workload to 1995, with a high ERA+ and over 6.0 WAR. The biggest difference was how they achieved their results: more strikeouts and fewer walks. Halladay symbolized this new generation of aces.2015
Aces: Zack Greinke, Jake Arrieta, Clayton Kershaw, Max Scherzer, Dallas Keuchel, David Price, Sonny Gray, Jacob deGrom, Madison Bumgarner, Felix Hernandez, Corey Kluber, Gerrit Cole.Ace’s Average: 17-8, 2.56 ERA, 218 IP, 172 H, 45 BB, 225 SO, 32 GS, 3 CG, 2 SHO, 156 ERA+, 6.1 WAR.MLB Starting Pitcher Average: 4.10 ERA, 7.4 SO/9, 2.73 SO/BB ratio.What defined an ace in 2015?: Strikeouts!Key statistic: Our aces’ strikeout rate rose to over one per inning.
This season had one of the best Cy Young races. The increase in strikeout rate reflects the beginning of the high-velocity era for pitchers. Arrieta and Greinke had multiple strikeout pitches along with their fastballs.2025
Aces: Paul Skenes, Cristopher Sanchez, Tarik Skubal, Hunter Brown, Garrett Crochet, Nick Pivetta, Freddy Peralta, Ranger Suarez, Zack Wheeler, Yoshinobu Yamamoto, Logan Webb, Max Fried.Ace’s Average: 13-6, 2.65 ERA, 174 IP, 137 H, 44 BB, 195 SO, 16 HR, 29 GS, 1 CG, 0 SHO, 162 ERA+, 5.4 WAR.MLB Starting Pitcher Average: 4.23 ERA, 8.2 SO/9, 2.77 SO/BB ratio.What defines an ace in 2025?: Dominance in shorter outings.Key stat: Aces have allowed zero or one run in 171 of 346 starts.
The workload has decreased, but these aces must dominate in shorter outings, often lasting only six or seven innings. Fewer innings mean fewer decisions and fewer wins for elite starters.
Although the days of multiple 20-game winners battling for the Cy Young are over, Skenes and Skubal, along with other outstanding pitchers, remain valuable. Skenes has 7.2 WAR, comparable to many of the best pitchers of 40 or 50 years ago.
Will Skenes’ 2025 campaign be as legendary as Gooden’s in 1985? No, but it’s important to appreciate what these players have achieved in a different era.
