From Tiger Woods Question & Answer session with the press during 2008 Masters:

"People have asked me what I enjoy most about practicing. I definitely like
chipping and putting, working on my short game. You can use your
imagination.

"I'm always testing golf balls. I don't ever put a ball in play unless I've
tested it pretty hard. Nike always keeps me informed about everything they
put out. I hit every club they make, whether it's game improvement clubs all
the way through to the wedges. I see everything and always have an idea
what's coming out. Obviously, a lot of it doesn't really suit the way I play
the game and what I like to do with the golf ball, but it helps a lot of
other players out. So that's the whole idea.

"It's also interesting to note that this is the first time I have played a
production ball, meaning you can buy the exact same Nike One Platinum right
off the shelf.

"If I make a bogey on the course, I'll sometimes change balls but not always.
If I scuff it, yea, it's out of play. Sometimes if I make a few birdies and
it's scuffed, I'm still keeping it until it runs out.

I mark my ball with a black line on the side. My ball says Tiger and it's
always a 1. I always played 1s on the first day and always played 1s on
Sunday. I had to play 2s and 3s on Friday and Saturday. Then when I switched
to the Nike ball, they allowed me to have all 1s and I said, 'Perfect'."

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