New England Patriots -- STADIUM SECURITY BEEFED UP ... Over Deflategate

Here's a bad joke based in truth ... cops are PUMPING UP security at Gillette Stadium for tonight's Patriots game ... over concerns stemming from Deflategate.

Sorry.

But seriously, the Massachusetts State Police Office of Media Relations tells TMZ Sports ... there WILL be an increase in personnel -- explaining, "With everything that's gone on in the off-season, we anticipate the fans will be more enthusiastic, more pumped up than usual ... a little feistier."

We're told the cops will employ the "playoff package" -- which is essentially an additional level of security.