If you want to know why the Dodgers jumped at signing outfielder Juan Rivera to a one-year, $4.5 million contract, consider this:

First baseman James Loney had the fifth worst OPS in the majors against left-handed pitching last season, right fielder Andre Ethier the seventh worst.

Rivera, by contrast, hits left-handers well. He also plays left field, right and first, as does another of the Dodgers’ right-handed hitters, Jerry Sands.

Thus, the signing of Rivera creates more options for manager Don Mattingly. Against certain lefties, Mattingly could sit his left-handed hitters, Loney and Ethier, and go with Rivera and Sands.

Ethier is a free agent after next season, and the Dodgers might be building enough depth to trade him. But that does not appear to be their intent with the Rivera signing; Rivera does not hit righties well enough.

No, the goal is simply a deeper, more flexible roster.

Dodgers center fielder Matt Kemp led the National League in OPS against left-handers last season, but the team overall ranked 11th in the 16-team NL.

Rivera helped after the Dodgers acquired him in a trade with the Blue Jays on July 12. The Dodgers went 25-10 in the final weeks, tying for the best record in the NL.

— Ken Rosenthal