By Daniel Chavkin Some unexpected visitors showed up on the field of Acrisure Stadium. When the Steelers played the Saints on Sunday, they received some unexpected visitors on the field. In the first quarter, as the Steelers were driving downfield, a flock of pigeons showed up on the other side of the field at Acrisure Stadium. The group of birds was shown digging for food on the field, but play continued as the players weren’t anywhere near the pigeons. Luckily, for both teams, the pigeons never interfered with play and had no impact on the score. As the game went on, the pigeons apparently d…