It’s no secret that the San Francisco Giants have one of the worst offenses in baseball this year. They’re ninth in the NL in batting average (.258) and dead last in runs scored (398), on-base percentage (.307) and slugging percentage (.691). Given how bad their offense is, the actors that played Roger Dorn, Jake Taylor and Pedro Cerano from “Major League” would compile a better lineup than the puss (save for Pablo Sandoval) that the Giants fill their lineup card with on a nightly basis.

So when you read or hear that San Fran traded for Pirates second baseman and ’06 batting champ Freddy Sanchez on Wednesday, it’s easy to think that the Giants just added the equivalent of Mickey Mantle’s bat to their lineup.

There’s no question that Sanchez is a dramatic upgrade over the players that San Fran has tried at second base this year, which include Emmanuel Burriss, Kevin Frandsen, Juan Uribe, Matt Downs and Eugenio Velez. And there’s no question that the Giants are better today than they were yesterday, just based on the fact that Sanchez will actually take pitches (something Giants hitters avoid at all cost), drive gaps and get on base.

But make no mistake: Brian Sabean still overpaid.

The Giants had four prospects that were seemingly viewed as untouchable when it came to trades: Buster Posey, Angel Villalona, Madison Bumgarner and Tim Alderson. If they were to give up any of those prospects this year, it would certainly only be in a deal that would net a big popper the likes of Victor Martinez or Matt Holliday (if you can even consider Holliday a “big popper”) – players that could get catcher Bengie Molina out of the cleanup spot for good.

But Sanchez is far from a big popper and Alderson, a 20-year-old pitcher who was viewed as the Giants’ fourth best prospect, was the price that Sabean had to pay to acquire the second baseman. It was too steep a price; Sabean once again panicked and once again overpaid for a veteran bat because he has compiled some of the worst offensive talent in baseball over the years.

And does Sanchez even fill a need for the Giants? The short answer is, “Yes, moron – have you seen how bad their lineup is?” But considering they needed a guy with power and not only didn’t get one, but also gave up a top prospect for a player in Sanchez who will probably find himself stranded on the base paths a lot in the second half was a questionable decision by Sabean.

I wouldn’t go as far as to say that the Pirates were the winners of this trade, but they certainly did well here. Alderson isn’t considered an elite prospect, but his command and control (two things that young pitchers often have trouble with) are outstanding and he’s a top of the rotation arm in the making. Sanchez wasn’t going to be a part of Pittsburgh’s future, so getting a potential NO. 2 in Alderson was fantastic coup for GM Neal Huntington.

Again, don’t get it twisted – the Giants desperately needed a bat and they got a solid one in Sanchez. But it’s surprising that Sabean had to give up one of his top trade pieces in order to get a guy in Sanchez who quite frankly, doesn’t fill the club’s most pressing need. Then again, nothing Sabean does in trades should surprise anyone since this was the same guy who traded away Joe Nathan, Francisco Liriano and Boof Bonser for one year of A.J. Pierzynksi. Sabean finds pitchers as if they were dropped off at this doorstep with the morning newspaper. But he would trade his wife, kids and mother just to acquire one mediocre veteran bat – and be happy as a pig in slop after doing so.