Andrew Luck remains sidelined with a nagging calf injury, but that hasn't kept him from throwing the football.

Luck has been working with throwing guru Tom House.

According to a source that has watched some of those throwing sessions, Luck is "throwing the absolute heck out of the ball," but is just not ready to take the next step.

The report emphasizes the difference between Luck's current calf injury and the shoulder issue that hampered him in the past.