Among the flurry of figures popping up is the less-known but pertinent "pitch count," which coaches track by the game and use as a major factor in determining how long a hurler stays in.

That count varies with individuals and often changes during the season, depending on such elements as climate, a pitcher's conditioning, and amount of rest between turns on the mound.

North Carolina pitching coach Scott Forbes puts an 85-pitch ceiling on a player's first outing in February, when the weather often is cold, then incrementally increases the number to about 100 after two weeks.

Pitchers in the regular rotation, who have six days between starts, eventually reach the 110-120 delivery range.

"You've got to watch them early, and you don't want to overtax them [anytime]," Forbes said. "We always believe in developing the bullpen. No. 1 is the kid's interest, and hopefully you can win at the same time. I couldn't sleep if I let somebody throw 150 pitches who might could sign a $2 million contract. Our responsibility is to take care of them."

The Carolina way has worked. The No. 1-ranked Tar Heels entered this week's ACC tournament in Jacksonville, Fla., with the nation's top earned run average (2.63).

In between mound appearances, the Tar Heels build stamina with assistance from trainers, strength and conditioning coaches, and a carefully calculated throwing program. Rest is a major part of the plan as well, Forbes emphasized.

"It's been helpful in keeping us healthy," said UNC's Adam Warren, who toiled 61 1/3 regular-season innings and posted an 8-1 record. "They take care of our arms so we can pitch later in the season."

Warren recalled a game at Duke when he wanted to work another inning. His arm felt strong, his confidence was soaring. But it was a cold day, and he was reaching his pitch limit, so Forbes went to the bullpen.

"Coach was looking out for my best interest,'' Warren said. "I'm glad I came to a program where they take [that] into consideration."

According to Baseball Digest, the origin of the pitch count is credited to former big league catcher and manager Paul Richards, who established it in the 1960s and set a safe delivery number at 100 per game.

That was a different mind-set from several moundsmen in those days. Sam McDowell and Sonny Siebert said they threw more than 200 pitches in some games, and Nolan Ryan reportedly fired 259 in a 12-inning game in 1974, Baseball Digest noted.

Tom Holliday, N.C. State's associate head coach and pitching coach, recalls emphasis on the pitch count heightening in the mid-1980s when agents became more involved and concern grew about the longevity of pitchers' careers.

Like most coaches, Holliday includes the pitch count in his criteria for maneuvering the Wolfpack's staff, which compiled a 3.36 regular-season ERA.

For example, if a Pack pitcher has three 20-pitch innings, he's likely to come out. And when a hurler gets in the 100 range, he's approaching the end of a day's play.

"If it's cold weather or early in the season, you keep the count down," said Holliday, who doesn't risk jeopardizing a player's career for a moment of glory.

How long a pitcher stays in depends on a variety of other factors as well, but pitch counts are now tallied from the Little League to the major leagues and show up in box scores. TV analysts also mention the number frequently on the air.

In 2007, Little League Baseball, concerned about protecting youngsters' arms, established a pitch-count rule for players ages 7-18 that also includes rest days between outings.

For example, Little League permits 75 pitches per day for players age 10 and under and 105 for 17- and 18-year-olds.

Then the rest rule kicks in. If a pitcher age 7-16 throws 61 pitches or more, he is required to get three days off before hurling again.

Minor league teams might adhere to the most stringent pitch count projection.

In last year's International League championship series, Richmond's Francisley Bueno had a no-hitter going through six innings against the Durham Bulls and was taken out after throwing 99 pitches.

"Everybody would have loved to have seen him go back out," manager Dave Brundage said. "[But] he was at his pitch limit. That's an organizational rule."

Richmond lost the game, but to the parent Atlanta Braves, pitching Bueno beyond his designated limit wasn't worth the risk of hurting the prospect's arm.

That's the trend, to count pitches instead of sheep.

Staff writer Chip Alexander contributed to this story.