Celebs trade barbs on baseball ‘Rivals’ ad

Keep an eye out for New Era’s “Rivals Are Forever’’ hat commercial during today’s broadcast of the Sox-Yankees game. In the spot, “30 Rock’’ star Alec Baldwin, an avid Yankees fan, squares off with “The Office’’ actor John Krasinski (inset), a Newton native and diehard Sox fan. The pair exchange some friendly trash-talking, including this Baldwin boast: “Classic Red Sox fan, go ahead and celebrate in April, we’ll dance in October.’’