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, April 27.

Rankings from last week are in parenthesizes.

1. (2) Atlanta Braves – 5.01

Injuries still haven't hampered the pitching staff, which ranks first in ERA, QS and BAA and second in WHIP.

2. (3) Milwaukee Brewers – 4.64

A clean Ryan Braun is still very good Ryan Braun. He's hitting .318/.361/.591 with six home runs and 18 RBIs.

3. (1) Oakland Athletics – 4.58

Josh Donaldson (1.6) has the fourth-most WAR in baseball.

T4. (6) Colorado Rockies – 4.03

Troy Tulowitzki is healthy (fingers crossed) and hitting .342/.449/.646 with five home runs and 17 RBIs.

-- (8) Washington Nationals – 4.03

Matt Williams has balance in Washington, D.C. The Nationals rank eighth in ERA (3.28) and ninth in OPS (.731).

6. (4) Los Angeles Dodgers – 4.02

Matt Kemp isn't hitting for average (.221), but there is still some pop in his bat (.500 slugging).

7. (12) St. Louis Cardinals – 3.84

A balky knee didn't bother Adam Wainwright against the Pirates on Sunday: 8 IP, 3 H, 0 R, 2 BB, 7 Ks

8. (16) Los Angeles Angels – 3.77

Albert Pujols hit the 500 home run plateau last week and is quietly having a bounce-back season.

9. (9) San Francisco Giants – 3.69

Brandon Belt, who entered the season with 33 career home runs, is on (a very early) pace to hit 45 homers in 2014.

10. (13) Kansas City Royals – 3.65

Did the Royals overpay for Jason Vargas (four-years, $32M)? He has a 1.54 ERA, 1.00 WHIP and 2.25 K/BB ratio through five starts.

T11. (5) Miami Marlins – 3.58

-- (7) Cincinnati Reds – 3.58

13. (11) Detroit Tigers – 3.53

14. (14) Texas Rangers – 3.44

15. (17) Boston Red Sox – 3.18

16. (18) New York Yankees – 3.15

17. (15) Tampa Bay Rays – 2.99

18. (10) San Diego Padres – 2.92

19. (21) Toronto Blue Jays – 2.84 

20. (20) Pittsburgh Pirates – 2.82

21. (22) Seattle Mariners – 2.76

22. (27) Philadelphia Phillies – 2.73

23. (23) Cleveland Indians – 2.72

24. (24) Chicago Cubs – 2.66

25. (19) Baltimore Orioles – 2.63

26. (26) Chicago White Sox – 2.62

27. (28) New York Mets – 2.47 

28. (25) Minnesota Twins – 2.42 

29. (29) Houston Astros – 1.64

30. (30) Arizona Diamondbacks – 1.46

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