Barrera is not in the lineup Friday against the Padres, Matt Weyrich of NBC Sports Washington reports.
Barrera has been seeing plenty of action with Yan Gomes (oblique) and Alex Avila (calf) sidelined, but he won't start the first game of the second half. Rene Rivera signed with the Nationals earlier in the day and will start Friday. Barrera and Rivera should split playing time behind the plate until Gomes or Avila is healthy.