Tony DeMarco

We interrupt this September stretch run to bring you … ’The Joba Rules’ and their innings-limiting brethren around the big leagues.

Here we are, in the midst of deciding postseason participants and their seeds, and teams — even those in the races — are putting shackles on pitchers who can help them get to where they want to go.

Seems at least a bit strange, doesn’t it? When you’re talking about heavy investments in young arms for both now and the future, teams’ protective interests are understandable, of course.

But the trick is finding the right balance of protecting the future while not doing too much damage to a team’s chances of advancing deep into this postseason.

The Yankees believe they are doing so with Joba Chamberlain, but others aren’t as certain. They have settled on the belief that he is in the rotation to stay — a wise choice considering how hard it is to find an overpowering arm with a full starting-pitcher repertoire. There just aren’t that many of those out there.

So to limit Chamberlain’s innings — and the basic rule of thumb here is to allow a young pitcher to increase only by about 30-40 innings from the previous year — they are capping his innings in each start.

The magic number for Chamberlain — who will turn 24 next week and is in his third big-league season — is 160 innings. Since August, the Yankees have kept him to five innings or less per start, and he is at 143.2 innings to date.

But look at the results: Through July 29 (the last start being eight shutout, three-hit innings), he was 8-4 with a 3.58 ERA. And in eight abbreviated starts since: 1-3, 7.09 ERA.

Are those recent numbers a reflection of the fact that he already was worn down, and needed the reduced work load? Or, has the reduced work load, and loss of consistency and location with his pitches, at the root of the inflated numbers?

Nobody knows for sure, but what is known is that the Yankees have chosen to rein in a 24-year-old power arm that could help lead them to a World Series title — with poor results to date.

You don’t have to be the Yankees to be employing this strategy. Even the Pittsburgh Pirates, who are about as far from contending as a franchise can be, are limiting Ross Ohlendorf, 27 and in his first full season as a big-league starter. It’s happening elsewhere, too.

But the other side of the coin would be the Texas Rangers. This one comes down from the top — team president Nolan Ryan, who in his day, thought nothing of a 150-pitch outing. Then he’d get up the next day, and do the heaviest weight-lifting workout in his training regimen.

You can’t argue with the results — not when he threw seven no-hitters (three more than anybody else), 12 one-hitters and struck out more hitters than anybody else ever will.

So throughout the Rangers system, pitchers are being pushed harder in their weightlifting and conditioning programs, and harder on the mound, where they are being asked to stretch it out and throw more innings and pitches.

Not exceedingly so, of course, but the bottom line is to do away with the six-innings-and-leave-it-to-the-bullpen mentality that has been allowed to creep into the game.

And in case you haven’t noticed, the Rangers are enjoying their best pitching results since their run of playoff appearances in the late-1990s.

As heavy as Ryan’s influence is, pitching coach Mike Maddux is the one who is executing the philosophy on the field and in the bullpen sessions. And remember that Maddux’s more-famous younger brother was one of the most-successful practitioners of another throw-often philosophy from a decade ago.

That would be the Leo Mazzone idea of throwing two side sessions between starts — rather than the traditional one — the thought being that control is sharper when you throw more often. (The corollary to that was mastering command of the fastball on the outer third of the plate, down in the strike zone.)

But it isn’t just the Rangers who are letting young and healthy arms stretch it out a bit. The San Francisco Giants didn’t limit Tim Lincecum on the way to his breakout, Cy Young Award season in 2008 at age 24, even though his 5-9, 170-pound frame belies his success.

And the Colorado Rockies have had no limitations whatsoever on emerging star Ubaldo Jimenez, who threw 198.2 innings in 2008 at age 24, and will cross the 200-inning threshold as the Rockies head back to the postseason for the second time in three years.

Nope, no ‘Timmy Rules’ by McCovey Cove, or ‘Ubaldo Rules’ around Coors Field.