“Mad Men” star Jon Hamm shot some unhappy looks at the bar TV at Masa on Wednesday night. The diehard Cardinals fan (he was born in St. Louis) was at the South End restaurant for the Huntington Theatre’s afterparty for “The Power of Duff,” which features Hamm’s longtime partner, actress Jennifer Westfeldt. Hamm skipped Game 1 to see the play, but was expected to be at the ballpark Thursday night. The Huntington crew finished Wednesday’s performance early enough to catch the last two hours of the game, when the Red Sox were up 5-0. Westfeldt told party-goers that she’s a Cards fan by association and that Hamm has been wearing his St. Louis cap around the city — much to the dismay of passersby. Joining Hamm and Westfeldt at the party for “Duff” — which runs through Nov. 9 at the Calderwood
Pavilion — were Westfeld’s costars
David Wilson Barnes (who plays the controversial newsman character Charles Duff), Ben Cole, Noah Galvin, and Joe Paulik. Barnes was with his agent Brian Davidson, while Westfeldt and Hamm brought Westfeldt’s mom, Connie Perelson, of Guilford, Conn.