TOWER GROVE — The Cardinals are close to acquiring a new face while continuing a familiar trend.

Late last night the news broke, by Joe Strauss here at The Post-Dispatch and by Padres beat writer Tom Krasovic over at the San Diego Union-Tribune, that the Cardinals had traded for San Diego shortstop Khalil Greene. Greene will become the St. Louis Cardinals’ fourth different everyday shortstop since the start of the 2004 World Series. And, his contract gives every indication that he could just be coming in as a bridge to the fifth different everyday shortstop between 2004 and 2010. Greene is owed $6.5 million this next season, and he will be a free agent next winter.

Should be OK. The Cardinals are used to a carousel at the pivot. They have plenty of practice rifling through middle infielders each winter.

Since Fernando Vina started 149 games at second base, Edgar Renteria started 147 games at shortstop, and both won a Gold Glove at their position in 2002, the Cardinals have played musical chairs with their middle infield. A tandem hasn’t started more than 135 games together sincce 2002, and the Cardinals have had a dozen different infielders start at least 30 games at the position — not double-counting shortstop Aaron Miles who started 33 games there in 2007 and second baseman Aaron Miles who started 63 games there the same season. And lest we forget Junior Spivey.

The closest the position has come to being stable is from 2004 to the 2005 when four players started at least 125 games each at the position.

Of course, it was two different sets of double-play tandems.

A nostalgic trip through the names that have come and gone in the middle infield:

2003: 2B Bo Hart (65), 2B Miguel Cairo (33), 2B Vina (58); SS Renteria (154)

2004: 2B Tony Womack (125); SS Renteria (148)

2005: 2B Mark Grudzielanek (132); SS David Eckstein (154)

2006: INF Miles (104); 2B Ronnie Belliard (53), 2B Hector Luna (35); SS Eckstein (119)

2007: INF Miles (96); 2B Adam Kennedy (74); SS Eckstein (112)

2008: 2B Miles (49); 2B Kennedy (74); SS Cesar Izturis (110)

Greene, who will turn 30 in October, once was the prototype for a fixture at shortstop. He has been the Padres’ starter there since 2004, had a season in 2007 that put him alongside the generation of standout shortstops in the National League (i.e., J.J. Hardy, Troy Tulowitzki, Stephen Drew, and the stockpile of stars in the NL East), and fit that age for a long-term deal. It’s not like San Diego didn’t try. Greene turned down a four-year, $29-million offer from the Padres last offseason — and then had a disastrous 2008 that ended with a frustration-powered punch and a fractured hand. (There is a grievance pending because the Padres argue they shouldn’t pay him for time missed for a “self-inflicted” injury.)

Back during the Spivey era, I wrote a story about the rotating cast of players the Cardinals had called on to play second base. Spivey was supposed to be the third reclamation project in three seasons, following Womack and Grudzielanek. Said two Cardinals officials still with the club:

Manager Tony La Russa said: “The situation has been a good one for all parties. Each of the guys that have gone on — Tony and Mark — they were good for us, and we were good for them. It’s not my favorite way to go. … It’s just a position that’s been in transition for us.”

Then assistant general manager John Mozeliak said: “It may seem like it, but it’s not a strategy. Is there a risk to running that model year after year? Sure.”

There was a brief moment in time when the Cardinals seemed on the verge of providing stability in the middle infield. Eckstein had a three-year extension offer on the table just as Kennedy was starting the first year of his three-year deal. While the Cardinals acknowledged that the pool of candidates for those positions was such that they could keep costs low by using a rotating cast, they did have interest in ending the constant rotation of new faces.

It hasn’t happened. In fact, it’s gone from only second to now also shortstop.

Greene is not unlike several of the other infielders the Cardinals have brought on a one-year revival. Womack. Grudzielanek. Izturis. He’s coming off a down year. He’s looking to regain some career traction. If the deal is completed, he’ll get playing time. And he could be gone after one year.

It’s not the stability at shortstop that the Cardinals may crave.

And it’s not like the Cardinals have a surefire answer on deck. Tyler Greene, drafted and groomed as a shortstop, was added to the 40-man roster recently and will get his first taste of big-league spring training. He’s reclaimed his prospect tag, but could just as easily be the solution at second base if he is more consistent as a hitter. Down the chain there’s Pete Kozma, the first-round pick in 2007, who is a steady glove making a deliberate climb through the system. (Greene is currently the leader for No. 17 in the Bird Land Community Top 30 prospect rankings, and Kozma has spurred plenty of discussion during the ongoing vote of readers.) Greene’s contract gives the Cardinals flexibility for 2010. But it also means another year, another spin of the middle-infield roulette.

Guess there’s always that increasing chance Kennedy is back as the starter at second.

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Multimedia multitasker Bernie Miklasz takes you through all of the statistics that make up Greene in his blog, Extra Points — an entry filed just as the breakfast crowd starts shuffling in at South City Diner. … Here is a retro feature from his turn as a college baseball star at Clemson. … Greene is a follower of the Baha’i faith, and it is reflected in his name: Khalil means “friend of God” and his middle name, Thabit, means “steadfast”. There is more on Greene, his family and his faith in this feature story from his rookie year. In it, Greene said: “I feel that if I accept the fact that what I do brings happiness to people and they enjoy watching me play, then I feel that in itself is a form of worship. We’re taught in (the Baha’i) faith that your work can be a form of worship. I try to do that and play the game like it’s meant to be played.”

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