Major League Baseball finally punished a San Francisco Giants left fielder for using performance enhancing drugs, and it wasn’t Barry Bonds. Melky Cabrera, who currently leads the Majors in hits with 159, will miss the rest of this season.

Looks like Andrew Baggarly was onto something back when he reported hearing a rumor that Cabrera had tested positive. With that rumor becoming fact today, he filled us in on where that whispers came from:

Cabrera was the MVP of the All-Star Game and has been the Giants’ most durable (and, at times, best) position player since he was traded to San Francisco for Jonathan Sanchez. He also inspired the whole “Melkmen/Melkmaids” fad and quickly became a fan favorite, seemingly driving his price this winter to Rowandian levels as he nears free agency.

Cabrera lost untold millions today. There will be no further appeals in this case, but Cabrera is eligible to play postseason baseball after the Giants play their 45 remaining regular season games and five playoff games. But without Cabrera, are these Giants a playoff team?

With the timing of this suspension, the Giants’ place in the standings (currently tied for first in the NL West with the Dodgers), and the player involved (a guy who was going to get some MVP votes … until today happened), this PED suspension has to be considered the most damaging to a team in U.S. professional sports history.

It’s also the second suspension after a positive drug test that the Giants have been hit with this season, as Guillermo Mota was suspended for 100 games after testing positive for Clenbuterol. Mota is eligible to return to the club on Aug. 28.

Tuesday night was the first time the Giants had their “optimal” lineup, with Cabrera, Buster Posey, Pablo Sandoval and Hunter Pence anchoring what, for the first time in a while, was a pretty formidable middle of the order. It might also be the last. Here is the Giants’ statement on Cabrera’s suspension:

“We were extremely disappointed to learn of the suspension of Melky Cabrera for violating Major League Baseball’s Joint Drug Prevention & Treatment Program. We fully support Major League Baseball’s policy and its efforts to eliminate performance enhancing drugs from our game. per the protocol outline by Major League Baseball’s collective bargaining agreement, the Giants will not comment further on this matter.”

Today’s happenings

— I got here late this morning, but I hear Bruce Bochy’s pregame media session was moved up a half hour. Cabrera was not discussed. Then the clubhouse was closed.

— Cabrera was in the lineup, batting third. That lineup has now changed to this: Pagan CF, Theriot 2B, Sandoval 3B, Posey C, Pence RF, Belt 1B, Blanco LF, Crawford SS, Lincecum RHP.

— One of the weirder things about what has been a very strange morning/afternoon: after hearing the news of Cabrera’s suspension, the press box was abuzz with people shouting questions, typing furiously, etc. On the field, Tom Tolbert, Brian Murphy and their teams were on the field hitting lazy fly balls in a HR-free “HR Derby” event.

Longer-term effects

One has to wonder if the Giants traded for Hunter Pence as a sort of insurance policy, although Nate Schierholtz (who is on the DL with a broken big toe) could’ve provided extra depth — although it wasn’t like he was mashing from April through July. Gregor Blanco is in the middle of an 0-for-18 slump currently, and the Giants seem very reluctant to rush Gary Brown (currently in Double-A) to the Majors.

Then there’s Aubrey Huff…

My prediction would’ve been that the Giants would sign Bobby Abreu, but he accepted an assignment from the Dodgers to Triple-A Albuquerque after clearing waivers.

Since Xavier Nady is hitting .138 in Fresno, the guy sitting next to me right now (Alex Pavlovic) is probably right, unfortunately — the best bet for OF help is Justin Christian, who looks like the prototypical Quadruple-A player when he’s in San Francisco but has a .348/.414/.515 slash line in Fresno.

Even harder to determine than how the Giants will replace Cabrera is what this does to the already flimsy idea that players can, with the right motivation and determination, transform their bodies (and their statistics). Cabrera was terrible in Atlanta during the 2010 season, then hit .305 with 201 hits for Kansas City last year. A commitment to fitness was cited by many, and until Baggarly dropped that rumor on everyone (which really upset several members of the team at the time), nobody thought PEDs played a role in Cabrera’s rise from slacker to All-Star. Now that stigma will follow Cabrera his whole career, and further the notion that whenever a player has an abnormal spike in production, it’s not due to an attitude change or natural means … like drinking one’s milk, for instance.