JSOnline.com reported yesterday that the Packers will be wearing a third, alternate jersey during the upcoming season. The report says it’s guaranteed for one game, but may make another appearance. The blurb doesn’t offer any information but does point out that Uni Watch was the first to break the info. Today, Clay Matthews tweeted asking if anyone knew anything about the jerseys, and dropped the hint that they’re from the 1920s era. According to JS, the uniforms will be unveiled on Friday at 4 pm at Packers Fan Fest.