Who is the greatest player in the history of each Major League franchise? Before we get to the answer, let’s be clear about the exact nature of the question.

What we’re not asking: Which player has enjoyed the most success with each franchise, sitting atop its all-time leaderboards and becoming synonymous with the team itself?

What we are asking: Which player who has suited up for each franchise at some point -- even very briefly -- had the greatest career? In other words, a legend who spent 20-plus seasons with a given team is considered just the same as one who made a 20-game cameo.

As for how to define “greatest,” we’re working off the all-time wins above replacement (WAR) leaderboard at Baseball Reference, knowing that while it’s far from a perfect metric, it’s the best, most objective single number we have for comparing players across the long arc of baseball history.

There are 19 different players who qualify as the greatest for at least one franchise by our criteria, with some being obvious and others quite surprising. The list includes nine players who did so for multiple franchises, two of whom tied for the most, with three apiece.

And with that, let’s get to it.

Braves, Red Sox, Yankees: Babe Ruth
Ruth’s WAR rank: 1st (182.6)

Of course you know of the Bambino as a Yankee. And his time with the Red Sox early in his career is an essential part of his story. But the Braves? Yes, that really happened, too. It was 1935, the Braves were still in Boston, and Ruth had turned 40 years old. Although he would add six home runs to his total as a member of the Braves -- reaching 714, a record that would stand for almost another 40 years -- Ruth’s return to Boston was ultimately a disappointing final chapter in a legendary career.

Honorable mentions: Hank Aaron (Braves), Ted Williams (Red Sox), Lou Gehrig (Yankees)

Twins/Senators: Walter Johnson
Johnson’s WAR rank: 2nd (165.1)

The Big Train pitched his final game almost 100 years ago -- and 34 years before the original Washington Senators moved from D.C. to Minnesota and became the Twins. Pitching in a far different era, Johnson racked up an all-time record 110 shutouts -- more than the number thrown by all MLB pitchers combined from 2019-23.

Honorable mention: Rod Carew

Cardinals, Guardians: Cy Young
Young’s WAR rank: 3rd (163.6)

The franchise Young actually pitched for the most was the Cleveland … Spiders. That was in his first nine seasons, from 1890-98, when the Spiders were an NL club. Yet the team’s owners also owned the NL’s St. Louis franchise, which soon would become known as the Cardinals. After the 1898 season, Cleveland’s top players (including Young) were transferred to St. Louis’ roster, after which the Spiders went 20-134 and folded. Young, however, continued to thrive. Even at age 42 in 1909, he threw nearly 300 above-average innings for the Cleveland Naps (now Guardians).

Honorable mentions: Stan Musial (Cardinals), Nap Lajoie (Guardians)

• Why the Cy Young Award was named after Cy Young

Giants, Pirates: Barry Bonds
Bonds’ WAR rank: 4th (162.8)

Bonds wound up spending 15 of his 22 seasons in San Francisco, but it’s worth remembering that he was an elite player before he got to the Bay Area. He posted at least 8 WAR in each of his final four seasons in Pittsburgh, winning two NL MVP Awards, three Gold Gloves and three Silver Sluggers.

Honorable mentions: Willie Mays (Giants), Honus Wagner (Pirates)

Mets: Willie Mays
Mays’ WAR rank: 5th (156.1)

It’s a funny quirk of this particular exercise that Mays qualifies for the Mets (two seasons, 135 games) but not the Giants (21 seasons, 2,857 games), getting beat out by his godson, Bonds. While Mays was in his 40s and battling injuries by the time he finished his career in Flushing, he actually hit quite well for the Mets in limited duty in 1972 (145 OPS+ in 69 games).

Honorable mention: Tom Seaver

Athletics, Tigers: Ty Cobb
Cobb’s WAR rank: 6th (151.5)

Of Cobb’s 4,189 hits (second all-time), 3,900 came in 22 seasons with Detroit. Still, even at age 40-41 with the Philadelphia A’s, Cobb batted .343, second highest in franchise history (minimum 900 plate appearances). 

Honorable mentions: Rickey Henderson (A’s), Al Kaline (Tigers)

• 15 amazing Ty Cobb facts baseball fans should know

Brewers: Hank Aaron
Aaron’s WAR rank: 7th (143.0)

Like Mays, Aaron shows up for the franchise with which he spent the tail end of his career -- but not the one with which he built his legend. Of course, while Aaron was only a Brewer for two seasons, at ages 41-42 in 1975-76, he did spend the majority of his career in Milwaukee, which was home to the Braves from 1953-65.

Honorable mention: Robin Yount

Astros, Blue Jays: Roger Clemens
Clemens’ WAR rank: 8th (139.2)

The Rocket spent a combined 19 seasons with the Red Sox and Yankees, compared with five with the Astros and Blue Jays. That being said, his time in Houston and Toronto was quite successful, netting Clemens three of his record seven Cy Young Awards.

Honorable mentions: Jeff Bagwell (Astros), Dave Stieb (Blue Jays)

Cubs, Orioles/Browns: Rogers Hornsby
Hornsby’s WAR rank: 12th (127.1)

As great as he was as a hitter, Hornsby also excelled at ruffling feathers, and he was traded three times in less than two years, going from the Cardinals to the Giants to the Braves to the Cubs between December 1926 and November 1928. His first season in Chicago in 1929 was also his last great season, and Hornsby was more of a manager than a player with the St. Louis Browns (now the Orioles) from 1933-37.

Honorable mentions: Ron Santo (Cubs), Cal Ripken Jr. (Orioles)

White Sox: Eddie Collins
Collins’ WAR rank: 13th (124.2)

A Deadball Era hitting legend, Collins split his career between the A’s and White Sox and is one of the greatest players in the history of both franchises. Collins ranks fifth and fourth, respectively, on their all-time WAR leaderboards, to go along with his 3,315 hits.

Honorable mention: Frank Thomas

Phillies: Grover Alexander
Alexander’s WAR rank: 15th (119.3)

Alexander, also known as Pete, came up with the Phillies in 1911. He dominated the rest of the Deadball Era, before and after being traded to the Cubs following the 1917 season. Alexander also missed most of the ‘18 season to service in World War I. An Army sergeant, he spent several weeks at the front in France and returned to the States with lasting wounds, both physical and mental, although he continued pitching through 1930.

Honorable mention: Mike Schmidt

Mariners, Rangers: Alex Rodriguez
Rodriguez’s WAR rank: 16th (117.5)

In Texas and later New York, there were record contracts, AL MVP Awards, a World Series title, a season-long suspension and much, much more. But before all that, in Seattle, A-Rod was one of the most sensational young players baseball has ever seen. Take 1996, for example. As a 20-year-old shortstop, he led the AL in average (.358), doubles (54), total bases (379) and runs scored (141), while notching 215 hits, 36 homers and 123 RBIs.

Honorable mentions: Ken Griffey Jr. (Mariners), Ivan Rodriguez (Rangers)

Angels, Dodgers, Padres: Rickey Henderson
Henderson’s WAR rank: 19th (111.2)

You knew Rickey was going to play a significant role at some point, given the path of his tremendous career, which became nomadic as he sought to stick around in the big leagues in his later years. He actually played 359 games and stole 91 bases for the Padres over three seasons, but his Angels and Dodgers stints accounted for a combined total of just 62 games and 19 steals. The latter was his final MLB action, as a 44-year-old in 2003, although Henderson would play two more seasons of independent ball after that.

Honorable mentions: Mike Trout (Angels), Clayton Kershaw (Dodgers), Tony Gwynn (Padres)

Reds: Tom Seaver
Seaver’s WAR rank: 22nd (109.9)

Seaver did his finest work as a member of the Mets, earning all three of his Cy Young Awards, all three of his ERA titles and his lone World Series ring. Still, he enjoyed some success in Cincinnati as well, following the June 1977 trade that was dubbed the “Midnight Massacre” in New York. Seaver threw his only no-hitter as a member of the Reds on June 16, 1978, blanking the Cardinals at Riverfront Stadium.

Honorable mention: Johnny Bench

D-backs, Nationals/Expos: Randy Johnson
Johnson’s WAR rank: 30th (101.1)

It’s hard to envision now, but the Big Unit began his career as a wild young pitcher in Montreal, making just 10 starts for the Expos before getting traded to Seattle in 1989. He would pitch well enough for long enough that he was coming off a second-place NL Cy Young Award finish for Arizona in 2005, when the Expos moved to Washington. The first of Johnson’s two D-backs stints, from 1999-2004, yielded four Cy Young Award wins and a World Series title.

Honorable mentions: Paul Goldschmidt (D-backs), Max Scherzer (Nationals)

Rays: Wade Boggs
Boggs’ WAR rank: 43rd (91.4)

A local product who was drafted out of Tampa’s Plant High School, Boggs made his name as a five-time batting champion in Boston, then won a World Series ring in the Bronx. But when the then-Devil Rays entered the league in 1998, Boggs, who would turn 40 that season, jumped at the chance to return home. He wound up hitting the first home run in franchise history and reached the 3,000-hit mark there. Tampa Bay later retired his number and inducted him into its Hall of Fame.

Honorable mention: Evan Longoria (Rays)

Royals: Gaylord Perry
Perry’s WAR rank: 46th (90.0)

The Hall of Famer pitched just one of his 22 seasons for the Royals, and it was his last. In 1983, a 44-year-old Perry started out with the Mariners, was released in late June, soon signed on with Kansas City and made 14 more starts that year, even managing to play a role in the infamous Pine Tar Game. There was still a bit of magic in that right arm, too. In the first game of a doubleheader on Sept. 3, at Texas, Perry tossed a shutout in the 687th of his 690 career starts, for his 314th and final victory.

Honorable mention: George Brett

Rockies: Larry Walker
Walker’s WAR rank: 91st (72.7)

After six seasons with Montreal, Walker signed with Colorado ahead of the 1995 season and went on to become one of the greatest players in franchise history over a 10-season tenure. He is the lone Hall of Famer to have suited up for the Rockies, although former teammate Todd Helton could join him in 2024.

Honorable mention: Helton

Marlins: Tim Raines
Raines’ WAR rank: 107th (69.4)

When Raines first broke into the Majors with the 1979 Expos, the Marlins were still 14 seasons from entering the league as an expansion team. By the time Raines played 98 games for them in his MLB finale at age 42, the franchise was already in its 10th season, with a World Series title to its credit and another coming the next year.

Honorable mention: Giancarlo Stanton