TOWER GROVE — Wrote recently about how Mark Mulder settled on his lower arm slot after first joking about slinging the ball from the sidearm and remaking himself as a wily lefty specialist coming out of the bullpen. As he thought more about it, the idea to drop his arm began to take root and germinate.

Now he’s throwing from a different slot, when he’s throwing.

So, about that second part of Mulder’s joke …

Hall of Famer Rick Hummel detailed the current blown-save shambles of the Cardinals bullpen in today’s paper and on Thursday lefty Randy Flores went on the disabled list with a swollen left ankle. One of the reasons the Cardinals’ bullpen appears to have frayed recently is the unsettled nature of its relievers roles. Kyle McClellan is the setup righthander, except when he’s not. Ron Villone is the lefty specialist, except when he’s not. Flores was the late-inning, lefty lockdown, except when he wasn’t. Jason Isringhausen isn’t the closer, Ryan Franklin is. For now. Etc. Etc. Injuries, inconsistencies and sheer usage have scrambled the cohesion that made the bullpen a strength just a few weeks ago.

Columnist Bernie Miklasz was earliest – and 4 a.m. is really early! — to dissect the bullpen, doing so recently at his juggernaut blog. He makes the point that Flores has struggled against lefties and righties, and that Villone has done well as a lefty specialist, or LOOGY. So, the Cardinals — in their quest to settle the bullpen by settling on its roles — must decide:

• Does Villone and his .159 BA against for lefties mean he’s the specialist?
• Does Villone’s ability to shoulder innings mean he’s the long-inning guy?

But an alternative should be looked into. How can the Cardinals spell relief?

M-U-L-D-E-R

The lefty was not strong enough in a bullpen session at Detroit to merit starting Saturday against Kansas City, as hoped. That means his major-league return has been pushed back — but do the Cardinals really want it to be against the New York Mets or Chicago Cubs, this week’s approaching opponents? (We’ve seen that Mets game before.) This is probably not the time for Mulder to make the 203rd start of his career.

But it could be right for his 203rd appearance, his first in relief.

For numbers of reasons, the big lefty’s splits against lefthanded hitters don’t offer much help in how he would fare as a reliever. Some select splits:

2006 vs. Lefties … .241 BA/.299 OBP/.361 SLG … 19 K, 5 BB, 83 AB

2005 vs. Lefties … .201 BA/.283 OBP/.317 SLG … 30 K, 15 BB, 139 AB

Last 3 yrs. … .227 BA/.296 OBP/.369 SLG … 50 K, 20 BB, 233 AB

Career … .263 BA/—- OBP/ —- SLG … 212 K, 86 BB, 1,046 AB

These numbers are skewed many ways. First, the kind of lineups Mulder mostly saw. Second, most of the stats are from when Mulder would acknowledge he was a different pitcher — some from when he was healthy (career), some from when he was pitching through problems (2006). He has described his current arm slot as not all that different from how he threw with Oakland, but it’s enough to possible dismiss his pre-surgery statistics. So read into them cautiously.

What could spur the Cardinals to consider Mulder as a bullpen option goes beyond the wish to recoup something from their investment, goes around the numbers above, even trumps the Cardinals need for a goose to the bullpen. It starts where so many things do nowadays for Mulder: With his recent rehab assignment.

Before skipping his scheduled third rehab start with back spasms, here is how he did:

• For Springfield, June 14 — 5 ip, 5 h, 0 er, 3 k, 0 bb 

• For Memphis, June 19 — 3 2/3 ip, 10 h, 6 er, 3 k, 2 bb

As with any rehab start, the truth is found beneath the box score. It’s almost better to go batter-by-batter, even pitch-by-pitch to judge a rehabbing pitcher. There’s so much the line doesn’t say: Velocity? Total groundballs? Bloop hits? Frozen ropes? Movement? Those aren’t columns in most box scores. But, when it comes to Mulder, a look at the batter-by-batter in these two rehab starts — with the new arm angle — does reveal something.

He’s cooled lefthanded hitters.

In his 8 2/3 innings on his recent rehab start, Mulder had seven at-bats against a lefthanded hitter. Triple-A Albuquerque had two lefties in the lineup against Mulder; Northwest Arkansas had one. Here is how each did:

vs. NWA

1st inning, Kila Kaaihue … Foul 91 mph; Foul 91 mph; Struck out looking. Curve.

4th inning, Kaaihue … Foul 90 mph; 3u, bounced out on curve.

vs. ALB

1st inning, Lorenzo Scott … Six-pitch, called strike 3.

1st inning, John Baker … Four-pitch, infield single to second base.

1st inning, Scott … First-pitch swinging, groundball single to right field.

2nd inning, Baker … Two pitches, 4-3.

3rd inning, Scott … 10-pitch, swinging strikeout, K 2-3.

It’s a tremendously small sample size and not the level of hitter that he would have to face in the role, but against lefties Mulder has held them to a 2-for-7 line with three strikeouts, no walks, two groundball base hits. In the game at Springfield, he was able to riddle the lefty with his curve coming out of the 2 o’clock arm slot that he’s been working on. He also was able to locate his sinker to what would be the inside edge of the plate to a lefthander.

It may not be feasible, or even agreeable, but it’s at least something to think about.

***

UPDATE 5:20 p.m.: This evening the Cardinals have activated Mulder from the disabled list and added him to the major-league roster. Look for coverage on StlToday.com and in The Post-Dispatch for how the Cardinals plan to use the lefty.

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