Why Hermida might not want to unpack too fast

The Red Sox acquired outfielder Jeremy Hermida from the Florida Marlins on Thursday for a relative pittance -- lefty reliever Hunter Jones, who made a couple of cameos with the Red Sox this season, and lefty reliever Jose Alvarez, who had a 4.74 ERA at Single-A Salem this season.

But that doesn't mean Hermida is a lock to go to spring training with the Red Sox -- let alone to play next season at Fenway Park. Among the reasons why:

1. He's a lefthanded hitter
The Red Sox went into September, before roster expansion, with just four outfielders on their 25-man roster: Rocco Baldelli, Jason Bay, J.D. Drew and Jacoby Ellsbury. Baldelli was the fourth outfielder -- and his primary value was as a caddy for Drew against lefthanded pitchers.

Hermida, however, doesn't bring that niche value. Hermida hit .282 against righties last season and a meager .189 against lefties. Hermida provides insurance for the possible departure of Bay, but even if Bay does end up leaving, the three best Red Sox outfielders all would be lefthanded. That's not the type of flexibility Terry Francona usually enjoys.

(Drew didn't miss any extended time this season, and you'd better believe that's in part because the Red Sox gave him regular days off -- something that was easy to do when they were facing a tough lefty. If Baldelli isn't re-signed, the Red Sox almost certainly will be looking for a righthanded hitter who can thrive in a part-time role in right field against lefties.)

2. There isn't a clear roster spot for him
If the Red Sox do sign a righthanded hitting backup outfielder, be it Baldelli or someone else, Hermida suddenly would be competing with Casey Kotchman for a roster spot. Baldelli and Mark Kotsay went into last season as the fourth and fifth Red Sox outfielders, but Kotsay was replaced by Adam LaRoche and LaRoche was replaced by Kotchman.

Unless the Red Sox make a move with Kotchman, they won't able to carry five outfielders on their roster because they'll be carrying too many infielders.

3. He doesn't have to be tendered a contract
The reason the Marlins were so eager to dump Hermida for any little package of prospects was because the outfielder will earn somewhere between $4 million and $5 million in arbitration this fall. (He earned $2.25 million last season.)

Had the Marlins not been able to trade him, though, they likely would have declined to tender him a contract -- something the Red Sox still have the option of doing. If Jason Bay signs -- or even is giving an indication he'll probably sign -- Hermida all of a sudden would become redundant on a roster that already includes Drew, Ellsbury and Kotchman.

Remember how an injury to Baldelli left the Red Sox without a viable righthanded bat off the bench during the playoffs? That's what the roster would look like next spring if Hermida inherits Baldelli's job as its fourth outfielder.

The Red Sox have until Dec. 12 to decide whether to offer contracts to their arbitration-eligible players -- Hermida and Kotchman among them. Maybe they'll let Hermida walk. Maybe they'll let Kotchman walk. Maybe they'll package one or both of them in another trade.

What they've really acquired in exchange for a pair of lefty relievers is a young player with upside and little bit of flexibility with their roster. That's it.

"This was not a blockbuster," Red Sox general manager Theo Epstein said. "This was a value trade, a chance to get a guy with unfulfilled potential for a reasonable cost. I don’t think we can draw grand conclusions about our offseason or the offseason throughout major league baseball based on this one transaction. It’s just a small move."

They've made no commitment to Hermida whatsoever. For all he knows, his Red Sox career might end up being as long and illustrious as that of Andy Marte.