The “lower leg” injury for Colts quarterback Andrew Luck continues to get more mysterious as the club remains vague about the nature of the issue and the long-term prognosis.

Luck appears doubtful to play in the preseason, and that's worth keeping an eye on for Chiefs fans. The Colts are due to visit Kansas City in Week 5 for a rematch of last year's Divisional Playoff game, and the game looms as a likely playoff bellwether for both teams, assuming Luck is healthy.

Colts GM Chris Ballard shares more details on Andrew Luck's injury: 'This is not 2017'