Ravens' Harbaugh optimistic Flacco will play Sunday

Baltimore Ravens head coach John Harbaugh said Monday quarterback Joe Flacco's "symptoms are zero," adding, "I think there's a good chance he'll play," according to the team.

Flacco was forced from Thursday's game against the Miami Dolphins and almost immediately placed in the league's concussion protocol after taking a big hit to the head.

He was replaced by backup Ryan Mallett, who went 3-for-7 for 20 yards and a touchdown.