The Opsera is a statistic RealGM Executive Editor Chris Reina created in order to objectively rank teams by how well they hit (OPS) and pitch (ERA). 

In order to determine the Opsera rating for each, we take their OPS, multiply that number by 10 to move the decimal point over one place to the right and then subtract their ERA from that number.  

All statistics are through Monday, May 26.

Rankings from last week are in parenthesizes.

1. (1) Oakland Athletics – 4.63

The Athletics endured a four-game losing streak last week, but rebounded to beat the Tigers 10-0 on Memorial Day. They lead our rankings for the second-straight week and continue to top the American League West.

2. (4) San Francisco Giants – 4.02

San Francisco has the best record in baseball and the third-best run differential entering Tuesday's action.

3. (3) Colorado Rockies – 3.92

The Rockies continue to hit well. Their .811 OPS has helped them overcome a 4.19 ERA.

4. (T7) Los Angeles Dodgers – 3.90

Everyone is waiting for the Dodgers to flip the switch again.

5. (5) Atlanta Braves – 3.89

If the Braves start hitting, the National League East race will be over very early.

6. (T9) Los Angeles Angels – 3.84

Los Angeles has been winning despite a rare slump from Mike Trout. That's a positive sign for the remainder of the season.

7. (T9) Milwaukee Brewers – 3.79

The Brewers have lost seven of their last 10 games as they fall back down to earth.

8. (2) Detroit Tigers – 3.68

How happy are the Tigers that they traded Prince Fielder for Ian Kinsler? Fielder is likely out for the season and Kinsler is hitting .330/.360/.477 with four home runs and 22 RBIs in 46 games.

T9. (T7) Miami Marlins – 3.67

Giancarlo Stanton, who served as Captain America on Monday, is an early National League MVP candidate. He's hitting .316/.404/.622 with 15 home runs and 49 RBIs.

-- (11) St. Louis Cardinals – 3.67

The Cardinals are a stronger offense away from another playoff run.

11. (6) Washington Nationals – 3.66

12. (16) Toronto Blue Jays – 3.64

13. (12) New York Yankees – 3.28

14. (T19) Pittsburgh Pirates – 3.20

15. (17) Cincinnati Reds – 3.18

16. (14) San Diego Padres – 3.17

17. (T19) Chicago Cubs – 3.15

T18. (22) Baltimore Orioles – 3.10

-- (23) Cleveland Indians – 3.10

20. (18) Seattle Mariners – 3.09

21. (13) Boston Red Sox – 2.97

22. (26) Texas Rangers – 2.95

23. (15) Kansas City Royals – 2.92

24. (21) Philadelphia Phillies – 2.86

25. (24) Tampa Bay Rays – 2.84

26. (25) New York Mets – 2.80

27. (27) Chicago White Sox – 2.71

28. (30) Houston Astros – 2.54

29. (29) Arizona Diamondbacks – 2.32

30. (28) Minnesota Twins – 2.30

 

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