McGrath (knee) was a limited participant in practice Thursday.
McGrath did not play in any preseason games after hyper-extending his knee in early August, so even limited participation is a good sign. If the 29-year-old is unable to play against the Broncos on Monday, rookie Sean Culkin is the only tight end on the Chargers' roster to fill the No. 3 role, which he likely earned in McGrath's absence anyway.