The first domino fell Thursday in what is expected to be a significant off-season overhaul of the Union’s roster. Veteran defensive midfielder Brian Carroll, a pillar of the team since arriving in 2011, announced that he will retire from playing after Sunday’s season finale against Orlando City (4 p.m., NBC Sports Philadelphia+).
Carroll is bringing down the curtain on a career whose longevity is nearly unparalleled in MLS history. Since his rookie season in 2003, the 36-year-old has played in 370 regular-season games, 20 playoff games, and 27 U.S. Open Cup games. He won MLS championships with D.