Arizona Cardinals free safety Tyrann Mathieu has said that he is sure that he will bounce back, despite suffering a horror injury which has ended his rookie campaign.

Mathieu must undergo surgery after he sustained a double anterior cruciate and lateral collateral ligament injury during Sunday's win over the St Louis Rams.

Cardinals coach Bruce Arians conceded on Tuesday that the injury 'could be a long one', but Mathieu said that he would not let it get him down.

He told reporters: "I've never been injured before, and to have my first injury be so severe I am sure it will take its toll on me as the months count down.

"I've been through enough already. Hopefully this can add some motivation into my life and let me reflect even more, grow closer to God and those type of things."

The Cardinals currently sit in third spot in the NFC West.