Cardinals face difficult roster decision

WATCH THE LATEST CARDINALS AND NFL VIDEOS FROM AZCENTRAL SPORTS(Photo: Photos by azcentral sports/AP)At some point this week the Cardinals could move a key player off injured reserve and begin to prepare him for a playoff run in December, assuming there is a run to be made.

Running back Chris Johnson and defensive back Tyvon Branch, placed on injured reserve with hernias on Oct. 4, are eligible to begin practice this week. Linebacker Alani Fua, placed on IR the week before with a knee injury, already was eligible.

All three have been mentioned as possibilities to be the one player the Cardinals are allowed to activate off injured reserve.

That player has to practice for two weeks before being…