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 Sunday, May 4.

Rankings from last week are in parenthesizes.

1. (3) Oakland Athletics – 4.42

The Athletics have the seventh-best OPS (.742) and third-lowest ERA (3.00) in baseball.

2. (9) San Francisco Giants – 4.19

Age is just a number for Tim Hudson, who is 4-1 with a 2.17 ERA and 0.74 WHIP.

3. (11) Miami Marlins – 4.18

The Marlins have an incredible one-two punch with Giancarlo Stanton and Jose Fernandez, but occupy last place in the National League East.

4. (5) Washington Nationals – 4.17

Washington is 6-3 without Bryce Harper, but that may not be sustainable. They are scoring nearly a full run less without the outfielder in the lineup.

5. (6) Los Angeles Dodgers – 4.03

A strong pitching staff goes better with week with the return of Clayton Kershaw.

6. (13) Detroit Tigers – 4.01

The Tigers jumped seven spots in our rankings thanks to a 5-0 week.

T7. (1) Atlanta Braves – 4.00

Julio Teheran, 23, is starting to flirt with the promise scouts expected. He has a 1.80 ERA, 0.88 WHIP and .200 BAA through seven starts.

-- (4) Colorado Rockies – 4.00

Nolan Arenado, who carries a 24-game hitting streak into the week, is hitting .311/.324/.492.

9. (2) Milwaukee Brewers – 3.92

Milwaukee has lost four of five after opening the season 20-7. They dropped seven spots in our rankings because of the slide, but still have a 5-game lead in the NL Central.

10. (12) Cincinnati Reds – 3.83

The Reds are the eighth NL team in our Top 10 as a number of expected AL contenders struggle.

11. (7) St. Louis Cardinals – 3.76

12. (8) Los Angeles Angels – 3.72

13. (15) Boston Red Sox – 3.54

14. (16) New York Yankees – 3.05

15. (14) Texas Rangers – 2.98

16. (24) Chicago Cubs – 2.97

17. (17) Tampa Bay Rays – 2.96

18. (22) Philadelphia Phillies – 2.89

19. (20) Pittsburgh Pirates – 2.86

20. (21) Seattle Mariners – 2.84

21. (19) Toronto Blue Jays – 2.83

22. (10) Kansas City Royals – 2.80

23. (25) Baltimore Orioles – 2.79

24. (18) San Diego Padres – 2.76

25. (23) Cleveland Indians – 2.74

26. (26) Chicago White Sox – 2.70

27. (28) Minnesota Twins – 2.42

28. (27) New York Mets – 2.40

29. (30) Arizona Diamondbacks –1.82

30. (29) Houston Astros – 1.69

 

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