I Always Wonder What Happens In Situations Like This

Professional athletes are no different than you and I when nature calls. So, what happens to you when nature calls when you are in the middle of a game?
Well, we found out what happens in baseball. From the New York Daily News: The count was 3-2 on Nick Evans in the top of the fifth inning Monday night when Angel Pagan realized he was needed on the field.
In the dugout, Terry Collins shrugged and began yelling for Pagan.
"They said, 'He's upstairs,' " Collins said, after Cliff Lee and the Phillies unloaded on the Mets for a 10-0 win.
"I said, 'Well, he's on deck.' I just thought he was doing something. Changing shoes. I don't know what it was."
Pagan was not changing shoes.
BOX SCORE: PHILLIES 10, METS 0
After Evans walked, and no batter appeared, home plate umpire Mike DiMuro strolled toward the bench. The crowd began to boo. The public address announcer waited.
Where was Pagan?
"I told the trainer, I have to go to the bathroom," Pagan said.
Turns out, the center fielder felt a rumble at the end of the fourth. It arrived suddenly, and with great force. Pagan said he informed trainer Ray Ramirez, and ran to the clubhouse.
http://www.nydailynews.com/sports/baseball/mets/2011/08/22/2011-08-22_philadelphia_phillies_thump_dillon_gee_and_new_york_mets_100_as_cliff_lee_rolls_.html
Baseball probably has it the best, they can go when they are in the dugout.
In football and basketball, I think I have seen it a couple of times- the player hustles off the court and returns in a few minutes.
But what happens if you are racing in NASCAR or in the Indy car series? Can't pull off the road and go. I can't imagine them peeing in a bottle lie truckers do.
If they have to go really, what happens? Pee or poop in their driving suit?
Or this real reason why we have start and parkers?