“But he won the Giants a World Series.”

That’s the response I get whenever I criticize San Francisco Giants general manager Brian Sabean. As if his one improbable World Series victory erases the blunders that the man has made before, after, and even during the Giants’ title season.

Yes, the Giants won a championship in 2010. But what does it say about Sabean when four of the top five players on his payroll were Barry Zito (who didn’t even make the postseason roster), Aaron Rowand (who shouldn’t have made the postseason roster), Edgar Renteria and Mark DeRosa (who didn’t make the postseason roster because of his wrist, which was held together by Elmer’s Glue when Sabean signed him in the offseason)? Sure, Renteria wound up being worth every penny of his $10,000,000 salary that year when he hit the eventual game-winning home run off Cliff Lee in Game 5 of the Series. But thanks to injuries and poor play, he was largely a non-factor in two seasons before that memorable home run.

Remember Cody Ross? Phillies fans sure do. Ross hit two home runs off of Roy Halladay in Game 1 of the 2010 NCLS and also hit a solo shot off Roy Oswalt in Game 2. If it weren’t for his bat, the Giants may not have reached the World Series that year, nevertheless won the whole shebang.

And Ross would have never made the postseason roster had Major League Baseball not conducted an investigation into Jose Guillen’s potential use of performance-enhancing drugs. Sabean acquired Ross that year in efforts to block any semi-productive player from going to the Padres, who at the time were leading the Giants in the NL West race. The fact that Ross wound up turning into “Ross the Boss” was more a product of luck than Sabean’s shrewd maneuvering. At one point, the Giants were thinking about putting Guillen (who ran like he had Oakland tied around his legs) on the postseason roster instead of Ross.

That spectacular pitching staff that the Giants currently boast wasn’t exactly all Sabean either. It was scouting director Dick Tidrow that gave such glowing reports on Matt Cain, Tim Lincecum and Madison Bumgarner. (Not to mention closer Brian Wilson and former top prospect Zach Wheeler, whom we’ll get to in a moment.) Granted, Sabean deserves praise for pulling the trigger on this players during the draft, but too often he receives credit for “finding” the talented arms that the Giants currently have in their starting rotation.

Which leads me back to Cain. It’s embarrassing to read some of the reports out of ‘Frisco these days about Cain’s contract situation. The 27-year-old right-hander is set to become a free agent after the 2012 season unless the Giants can hammer out a long-term deal, which apparently is more difficult than correctly picking every winner in the NCAA tournament. It was only recently that Cain suggested that he’s considering testing the market. Before then, he stated how he wanted to remain a Giant but Sebean has yet to come to terms with the soft-spoken starter, who has meant as much to the Giants as Lincecum. (Had Cain received more run support from that putrid thing Sabean calls a lineup every year, maybe he too would have challenged for a Cy Young by now.)

There’s simply no good reason for Sabean not to lock Cain up to a long-term deal. If the righty wants $100 million, then the Giants should oblige. I mean, why not? Sabean had no problem overpaying Zito, Rowand, DeRosa, Renteria and Miguel Tejada, but he’s going to balk at signing a productive player? Are you kidding me? If Cain doesn’t get $100 million from the Giants, he’ll find it on the open market next winter. Thus, if he truly wants to stay, then all Sabean needs to figure out is if he wants to see Cain in a Giants’ uniform next season, or in Yankee pinstripes. And while there’s plenty of time to hammer out a deal before now and November, players usually don’t like discussing their contract situation during the season. Thus, Sabean’s window to sign Cain is closing.

Let’s not forget that Sabean was also the professor who traded Wheeler to the Mets at the trade deadline last year for a two-month rental named Carlos Beltran. Then Sabean didn’t even attempt to re-sign Beltran this past winter, even though the Giants had the second-worst offense in terms of runs scored last season.

Granted, not every decision Sabean makes turns to sulfur and he does have to worry about surpasing Cain’s deal when Lincecum because a free agent after the 2013 season. But the philosophies behind some of his moves are absolutely mind-boggling. It’s almost like the guy wakes up and says, “What’s the least logical thing I can do today while running this baseball team? Trade Joe Nathan, Francisco Liriano and Boof Bonser for one miserable year of A.J. Pierzynski? Yes. Yes that sounds good.”

If Sabean loses Cain in November after already dealing Wheeler for what amounted to nothing in return, then Lincecum turns around and heads to Seattle to play for his hometown Mariners (which is a distinct possibility), maybe then people will drop the whole “But he won the Giants a World Series” bit.

Because if Cain isn’t in a San Francisco uniform next season, there will only be one man to blame.