The NFL is set to enforce its toughest rules yet for when players can return to games or practices after suffering head injuries. The new guidelines go into effect this week in the latest move by the league to address a hot-button issue.

For an analysis of the new concussion policy we spoke with Dr. Julian Bailes, chairman of neurology at the West Virginia School of Medicine and former team doctor for the Pittsburgh Steelers. He spoke to Kiran Chetry on American Morning Thursday.

It's the story everyone's talking about this morning: Golf great Tiger Woods and his car accident right in front of his Florida home.

Tiger is not talking. Cops have been told he has nothing more to say to them. Meanwhile there's a lot of speculation about what really happened in the moments before and after the accident and whether there's another woman in the middle of this mess.

Meantime police have released tapes from a 911 call that came from Tiger's neighbor moments after the incident. So with all the rumors swirling around Woods right now could this incident impact his career and all those lucrative endorsements?

David Dusek, deputy editor of Golf.com, spoke to Kiran Chetry on American Morning Monday.

Related: Woods: 'This situation is my fault'

For years he dominated the world of tennis. In his new book, Andre Agassi admits he actually hates the game. The memoir is called "Open: An Autobiography."

In the book, Agassi opens up about using Crystal Meth and a whole lot more. He joined Kiran Chetry and T.J. Holmes on CNN's American Morning Thursday.

Read an excerpt from Agassi's book

Open: An Autobiography
By Andre Agassi

EXCERPT – THE END

I open my eyes and don’t know where I am or who I am. Not all that unusual—I’ve spent half my life not knowing. Still, this feels different. This confusion is more frightening. More total.

I look up. I’m lying on the floor beside the bed. I remember now. I moved from the bed to the floor in the middle of the night. I do that most nights. Better for my back. Too many hours on a soft mattress causes agony.
I count to three, then start the long, difficult process of standing. With a cough, a groan, I roll onto my side, then curl into the fetal position, then flip over onto my stomach. Now I wait, and wait, for the blood to start pumping.

I’m a young man, relatively speaking. Thirty-six. But I wake as if ninety-six. After three decades of sprinting, stopping on a dime, jumping high and landing hard, my body no longer feels like my body, especially in the morning. Consequently my mind doesn’t feel like my mind. Upon opening my eyes I’m a stranger to myself, and while, again, this isn’t new, in the mornings it’s more pronounced. I run quickly through the basic facts. My name is Andre Agassi. My wife’s name is Stefanie Graf. We have two children, a son and daughter, five and three. We live in Las Vegas, Nevada, but currently reside in a suite at the Four Seasons hotel in New York City, because I’m playing in the 2006 U.S. Open. My last U.S. Open. In fact my
last tournament ever. I play tennis for a living, even though I hate tennis,
hate it with a dark and secret passion, and always have.

As this last piece of identity falls into place, I slide to my knees and in a whisper I say: Please let this be over.

Then: I’m not ready for it to be over.

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