Best MLB Rookie of the Year Winners

In 2012 Mike Trout wasn't just the best player in baseball, he was probably the best 20-year-old position player ever. Meanwhile, Bryce Harper, while not quite as productive, was only 19 years old, and arguably the greatest teenage position player in history. Never before had two players been so good, while so young, in the same season. Not surprisingly, each player was named the Rookie of the Year (ROY) for their respective league. Given their youth and talent, it's easy to imagine them as star players for years and years to come. If they do have that kind of success, where might they rank among all Rookie of the Year winners? Where might they rank as a duo, compared to all the other winning pairs?

The Rookie of the Year Award has been around since 1947, when it was created and given to Jackie Robinson. There was only one winner that year, and again in 1948. In 1949 a separate winner was named for each league, which is how it's worked ever since.

Rookie of the Year winning seasons, ranked by WAR*

t10) Nomar Garciaparra (AL, 1997) - 6.6
t10) Albert Pujols (NL, 2001) - 6.6
t8) John Montefusco (NL, 1975) - 6.8
t8) Tony Oliva (AL, 1964) - 6.8
7) Mika Piazza (NL, 1993) - 7.0
t5) Carlton Fisk (AL, 1972) - 7.3
t5) Fred Lynn (AL, 1975) - 7.3
4) Ichiro Suzuki (AL, 2001) - 7.7
3) Dick Allen (AL, 1964) - 8.8
2) Mark Fidrych (AL, 1976) - 9.6
1) Mike Trout (AL, 2012) - 10.9

*All figures in this post use Baseball-Reference's WAR calculations, sometimes called bWAR, and are updated through the 2012 season.

Rookie of the Year winners, ranked by career WAR:

10) Lou Whitaker (AL, 1978) - 74.8

9) Johnny Bench (NL, 1968) - 75.2

8) Pete Rose (NL, 1963) - 79.4

7) Jeff Bagwell (NL, 1991) - 79.5

6) Rod Carew (AL, 1967) -81.2

5) Albert Pujols (NL, 2001) - 91.5

4) Cal Ripken (AL, 1982) - 95.6

3) Tom Seaver (NL, 1967) - 106.3

2) Frank Robinson (NL, 1956) - 107.1

1) Willie Mays (NL, 1951) - 156.1

It would be foolish to predict that Trout or Harper will climb close to the top of that list. It's not that there's no chance of it happening, but the chances of it are so slim, even for players as talented as these two. The combination of Trout and Harper in the same year though, two winners so young and two winners so good, is particularly impressive. "So young" and "so good" might seem obvious for Rookie of the Year winners, but the typical winner may not be quite as young or as good as you think.

The median age among the 132 Rookie of the Year winners is 23. Young, but not 19 or 20. Harper was only the second 19-year-old to win the award (Doc Gooden being the other), while Trout was just the 8th 20-year old. Never before had both Rookie of the Year winners been 20 or younger. The only previous pair both 21 or younger were 1978's winners, Bob Horner (20) and Lou Whitaker (21). The median bWAR among all 132 ROY winning seasons is 3.35. That's a very good season, but far from Harper's 5.2 and a different realm entirely from Trout's 10.9.

Trout and Harper were just the eighth ROY pair ever to both collect 5+ WAR. That distinction, along with Trout's other-worldly season, makes their combined performance a candidate for the strongest of any pair. Dick Allen (8.8) and Tony Oliva (6.8) would probably get my vote, but it's close. What first started me researching previous Rookie of the Year winners was wondering how they might stack up with the other pairs of winners in the award's history, but not for their winning season, I'm talking about their career. Obviously it's too early to know what will happen, but the quality of their winning seasons paired with their being the youngest pair ever is intriguing.

The most obvious way to combine each season's two winners would be just to add their WAR together. Doing that though, any pair with one great winner would score very well. I'm trying to identify pairs where both players were strong. In 1982 the winners were Cal Ripken and Steve Sax, they combined for 120.9 WAR, sixth highest of any pair, but while Sax was a solid player (25.3 WAR), Ripken did the vast majority of the lifting (95.6 WAR). Willie Mays and I have combined for 156.1 WAR, but who cares?

Instead of adding them together, I'm going to find the harmonic mean of each pair's career WAR totals:

H = (2 * X * Y) / (X + Y)

(H = harmonic mean, X = NL winner's career WAR, and Y = AL winner's career WAR)

The harmonic mean weighs lower figures more heavily. 50 + 50 (pair A) and 90 + 10 (pair B) both = 100, but the harmonic mean of pair A would be much higher than that of pair B. This method will make it more important that both winners have had a strong career in order for the pairs score to be especially high, one player cannot do all the lifting.

Rookie of the Year winning pairs, ranked by harmonic mean of career WAR:

10) 1993, Mike Piazza (NL, 59.2) and Tim Salmon (AL, 40.6) - 48.17
9) 1964, Dick Allen (NL, 58.7) and Tony Oliva (AL, 43.1) - 49.70
8) 1972, Carlton Fisk (AL, 68.3) and Jon Matlack (NL, 39.1) - 49.73
7) 1997, Scott Rolen (NL, 70.0) and Nomar Garciaparra (AL, 44.2) - 54.19
6) 1991, Jeff Bagwell (NL, 79.5) and Chuck Knoblauch (AL, 44.5) - 57.06
5) 1951, Willie Mays (NL, 156.1) and Gil McDougald (AL, 40.6) - 64.44
4) 1977, Eddie Murray (AL, 68.2) and Andre Dawson (NL, 64.4) - 66.25
3) 2001, Albert Pujols (NL, 91.5) and Ichiro Suzuki (AL, 57.0) - 70.24
2) 1956, Frank Robinson (NL, 107.1) and Luis Aparicio (AL, 55.7) - 73.29
1) 1967, Tom Seaver (NL, 106.3) and Rod Carew (AL, 81.2) - 92.07

Pujols and Suzuki stand a pretty good chance of moving into the #2 spot before their careers are over (11 more WAR by Pujols or 4 more by Suzuki would do the trick. Ichiro looks about finished, but Albert ought to be able to pull that in), but they aren't going to get to #1. Among other active pairs, 2007's Ryan Braun and Dustin Pedroia are already at 32.53, so another 15 WAR apiece would put them on the list, while 2006's Justin Verlander and Hanley Ramirez are just a bit behind them at 31.15.

There you have it, the best Rookie of the Year winning pairs in baseball history.