Breaking down the free-agent class by the numbers

Breaking down the free-agent class by the numbers

Featuring multiple ace-caliber starting pitchers, this offseason's free-agent class is shaping up to be not only a star-studded one, but also a historic one.

Between Zack Greinke coming off one of the most dominant regular-season performances of all-time, fellow aces David Price and John Lackey hitting the open market, and a couple other veteran starting pitchers also testing free agency, this year's class is unlike any other in a number of ways. The following is a look at some of the most impressive facts and figures surrounding this offseason's crop of free agents.

• Greinke led the Majors this year with a 225 ERA+, while Price checked in at fifth with a 161 ERA+, and Lackey's 142 ERA+ placed him 10th. Those marks makes this year the first time that three pitchers with an ERA+ of at least 142 entered free agency in the same offseason.

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• This will also be the first free-agent class to feature multiple pitchers coming off a season in which they recorded at least 18 wins with a winning percentage of .750 or higher. Greinke went 19-3 (.864) over his 32 starts with the Dodgers, while Price went a combined 18-5 (.783) in his 32 starts between the Tigers and Blue Jays.

• Greinke's 9.3 WAR this past season is the highest all-time by any pitcher in a season preceding free agency. It's the highest by an impending free agent overall since 2007, when Alex Rodriguez racked up a 9.4 WAR before entering free agency and later re-signing with the Yankees.

• This is the first time since 2005 that the top pitcher from the previous season, based on WAR, will enter free agency. The most recent pitcher to do so was Roger Clemens, who led the Majors with a 7.8 WAR while pitching for the Astros during the '05 campaign. Despite interest from multiple teams that offseason, Clemens initially decided to retire before eventually coming out of retirement -- for the third time -- on May 31 the following year to return to Houston.

Greinke's 200th strikeout

• Along with Greinke sitting atop the leaderboard, Price and Lackey also finished among the top-10 pitchers this past season. Price's 6.0 WAR was the sixth best in the Majors, while Lackey's 5.6 mark ranked eighth. This is the first time since 2004 that three of the league's top 10 pitchers, based on WAR, will enter free agency together. The last trio to do so was Randy Johnson, Brad Radke and Pedro Martinez.

• This year's class boasts five pitchers -- Greinke, Price, Lackey, Johnny Cueto and Bartolo Colon -- who have had at least one season of 5.0+ WAR within the past three years. That's the most since the 2008 class, which had seven pitchers -- CC Sabathia, Mike Mussina, Ryan Dempster, Brad Penny, John Smoltz, Curt Schilling and Jason Jennings -- enter free agency after recording at least one 5.0+ WAR season from 2007-09. That said, both Mussina and Schilling ultimately retired instead of signing a new contract.

Price notches 17th win

• Including position players, there are six free agents coming off a season in which they racked up a WAR of at least 5.0. Along with the aforementioned trio of pitchers, Jason Heyward, Chris Davis and Yoenis Cespedes also surpassed the 5.0 WAR mark. The most recent time at least six players entered free agency coming off a season of 5.0 WAR or better was 2008, when Sabathia, Mussina and Dempster entered alongside Mark Teixeira, Manny Ramirez and Milton Bradley.

• Speaking of position players, Heyward (6.5 WAR) and Cespedes (6.3) are the first duo to enter free agency after each posting a 6.3 WAR or higher since 2010, when Adrian Beltre (7.8) and Carl Crawford (7.0) each did so.

Must C: Heyward's go-ahead homer

• In fact, the two position players entering free agency with a 6.3 WAR or higher are more than the past four offseasons combined. From 2011-14, the only position player to rack up that type of WAR and then test free agency was Robinson Cano, who tallied a 7.8 WAR during the '13 season before signing a 10-year, $240 million deal to join the Mariners that offseason.

Paul Casella is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.