“To see how the media can start a rumor and how the horses mouth can squash it, check out my fbk and RT,’’ the Giants’ Steve Smith tweeted Tuesday. Media? Well, Rotoworld, which said it had been told by “sources’’ that Smith would be going on the Physically Unable to Perform list and therefore was a bad choice in fantasy football.

“I’m feeling good, don’t listen to rumors,’’ Smith tweeted.

Who knows if Smith will be ready when the season starts? It may not matter anyway since right now as the two entrenched sides in the dumbest labor dispute ever do their best to leave us without an NFL this fall.

But the Rotoworld item illustrates what has happened to the media. In the age of newspapers, we were told to verify everything. Where I worked, we were supposed to stay away from unnamed sources or have at least two if someone insisted on anonymity. And to attempt to reach the people involved — in this case, Smith himself.

Today, we blurt out whatever we have, verified or not. Who might be a “source’’ on the state of Smith’s knee? A doctor? Only if he wants to lose his license. Someone on the Giants’ coaching staff or in the front office? Again, career-ending if discovered. A teammate or other player? Notoriously unreliable. An agent? Ulterior motives — Smith is one of the 900 or so NFL players in limbo, an unrestricted free agent under one scenario, a restricted free agent under another. He’s said he wants to return to the Giants and the Giants say they want to re-sign him, but spreading rumors about his health remains part of that game.

OK, write me off as an old-timer who dislikes new ways. Yes, I tweet (@davegoldberg84) because I find it a quick (if often inaccurate) news source. And I blog (that’s what I’m doing now.)

But there are things that bother me, as one did Saturday night when an often informative site called Awful Announcing (@awfulannouncing) handled the arrest of ESPN hockey analyst Matthew Barnaby by adding its own speculation about a third party, then left the original info in a second story when it discovered what it speculated was wrong. I was trained in “just the facts, ma’am,’’ on arrests. So we tweeted angrily at each other and finally settled our differences — they really are quite knowledgeable about broadcasting, so try them.

I’m not as hard on stuff like trade rumors, like the one about an alleged draft day deal between the Redskins and Steelers reported by the almost always accurate Peter King among others. Heck, back in the 1930s, ‘40s and ‘50s, baseball reporters used to spend the offseason making up possible trades and spreading false rumors in hopes that rivals would pick them up and get stuck with bad stories.

Back to Smith. A week or so ago, Pro Football Talk, another “new media’’ outlet, tweeted an item with the headline that “Steve Smith’’ might be traded. It neglected the first time to note whether it was the Giants’ Steve or the Panthers’ Steve.

It was, as I knew, Carolina Steve and PFT fixed it.

I like Pro Football Talk, which has mixed the old ways of reporting with some new ones and has become a very respected NFL voice.

But haste leads to mistakes (I know, I’ve made plenty because of it.)

So if there is a season ...

Don’t go to Rotoworld when you pick your fantasy team.