Danny Amendola out about 6 weeks

St. Louis Rams wide receiver Danny Amendola is expected to miss about six weeks with an injury to his collarbone, a league source told ESPN NFL Insider Adam Schefter.

Amendola, injured in Thursday's game against the Arizona Cardinals, suffered what the team believes is a sternoclavicular joint separation. While the injury is expected to sideline Amendola six weeks, he could return earlier.

Rams coach Jeff Fisher had little to say about the condition of Amendola, calling it a "competitive issue." Fisher said he'd have an injury report Wednesday regarding Amendola.

"If Danny's going to miss a game, I'll discuss it at a time at which I'm sure that he's going to miss a game," Fisher said Friday.

Amendola injured his shoulder on a diving attempt at a catch in the second quarter of Thursday night's 17-3 win.

A TV camera caught Amendola flinging his helmet into a wall with his left hand while walking in a tunnel to get X-rays. He had the arm in a sling after the game, but the Rams did not make him available to reporters.

Amendola had a 44-yard reception on the Rams' first drive, setting up a TD pass from Sam Bradford to Lance Kendricks. Amendola entered the game with 31 receptions, second in the NFL, with two TDs and an 11.3-yard average.

Amendola missed virtually all of last season after dislocating his left elbow in the opener.

Information from The Associated Press was used in this report.