Colts QB Anthony Richardson sidelined due to shoulder injury, replaced by Gardner Minshew

Indianapolis Colts quarterback Anthony Richardson left Sunday's 23-16 win over the Tennessee Titans due to an injury to his throwing shoulder and was replaced by backup Gardner Minshew.

Richardson was injured on a run in the second quarter. A hard tackle by Titans linebacker Harold Landry III drove his right shoulder into the turf. Richardson immediately tapped his shoulder with his left hand to indicate that he was injured.

He received medical attention on the field and left the game. Gardner Minshew took over at quarterback. The Colts announced that Richardson was being evaluated for a shoulder injury, then ruled him out at halftime. NFL Network's Ian Rapoport reported that X-rays on his shoulder came back negative. NFL Network's Tom Pelissero reported after the game that Richardson was initially diagnosed with an AC joint sprain in his shoulder and will undergo an MRI for further evaluation.

While we don't know what the MRI told them, the Colts are reportedly continuing to gather more information about their QB's injury. According to ESPN's Jeremy Fowler, Richardson is seeking a second opinion from well-respected shoulder specialist Dr. Keith Meister. Richardson is reportedly expected to miss this week.

Richardson, the No. 4 pick in April's draft, has had an explosive start to his NFL career as a dynamic threat to create big plays for the Colts offense using his athleticism and big arm. But the injury Sunday was his third in just five games.

He left the final drive of his NFL debut against the Jacksonville Jaguars after blows to his ankle and his knee. He was concussed in a Week 2 win over the Houston Texans. The concussion sidelined him for Indianapolis' Week 3 game against the Baltimore Ravens.

Richardson's aggressive playing style is the source of his upside, as he entered Sunday having recorded three passing touchdowns and four rushing touchdowns in three games. It also leaves him exposed to a lot of contact.

The nature of Richardson's injury wasn't initially clear, but it was concerning for the Colts and their first-round rookie.