What happened: Dallas had only two padded practices after returning from Arizona, making it difficult to assess Smith's thumb. The issue had lingered through most of camp before the Cowboys chose surgery Tuesday.
Why it matters: The decision removes an All-Pro guard as the regular season begins. Putting Smith on injured reserve would keep him out for at least four games.
By the numbers: Smith has earned three consecutive Pro Bowl selections and made 63 starts across four NFL seasons.
What to watch: Dallas must set its opening lineup and track Smith's recovery after the procedure.