Gennifer Durham's perfect pitch

Gennifer Durham began throwing the knuckleball simply as an off-speed pitch, but the Holy Cross coaches made it her primary pitch when they saw how effective it was. Graham Hays/espnW

WORCESTER, Mass. -- To throw a knuckleball is to concede imperfection, to strike a bargain with physics, where other pitchers try to bend the game to their will with pinpoint accuracy or overpowering speed.

A knuckleball isn't perfect; it's pragmatic. It need succeed only more than it fails.

A senior catcher on the Holy Cross softball team who also happens to major in physics, Kat Rosenthal has studied the science behind the pitch. She's the kind of catcher who can casually throw around terms like "rotational decay rate" or talk about the effects of drag on a smooth sphere.

"It changes planes faster than your eyes can move," Rosenthal said of the knuckleball. "Because of the way it moves, because it has no spin on it, it can literally drop and have no movement on it. It can just bottom out."

The unpredictable dance through the air is what befuddles batters about a pitch that otherwise approaches the plate with less velocity than a typical batting practice offering. It's also why the pitchers who throw it are as unsure of its path as the batters. Baseball Hall of Famer and knuckleballer Phil Niekro led the league in walks three times. Noted Boston Red Sox knuckleballer Tim Wakefield once led the league in home runs allowed and twice in batters hit by pitch.

So it's hardly a surprise that none of the 23 perfect games thrown in major league baseball history has been the work of a knuckleball pitcher.

But when Holy Cross freshman knuckleballer Gennifer Durham retired all 21 Colgate batters she faced on April 13, college softball experienced implausible perfection.

"It just felt like a normal day," Durham said of the second perfect game in Patriot League softball history. "I didn't feel anything out of the ordinary. It just happened to be a good day."

Pitchers who specialize in the knuckleball aren't exactly commonplace in baseball, but that sport is overflowing with them compared with college softball. Rosenthal had never seen one before Durham. At best, as with the case of Holy Cross coach Brian Claypool, coaches and players might vaguely recall seeing someone somewhere throw it a few times.

Part of that is physics. As Rosenthal explained, there are 108 seams on a baseball and only 88 seams covering considerably more surface on a softball. It's the interaction between seams and air that causes the knuckleball to flutter, meaning it's easier to throw with a baseball (a difference somewhat mitigated by the fact that softballs are left in play with more blemishes, thus more rough spots, than baseballs). Additionally, while the softball seams are bigger, the overall size of the ball makes it more difficult to grip in knuckleball fashion for someone with smaller hands.

Undoubtedly, the scarcity of the pitch in softball is also self-perpetuating. You need people who know how to throw it in order to have people who can teach it.

Growing up in South Carolina, Durham learned the knuckleball from one such person, Lacey Ingram, a pitching instructor in Atlanta and a former college pitcher at Georgia Southern. By the time Durham was in middle school, she was throwing it as her change-of-pace pitch.

"It wasn't that difficult; it was just different," Durham said of the learning process. "I couldn't really throw a changeup until then, and so that one actually worked better from me."

Durham was a decorated high school player at the small-school level in South Carolina, but she wasn't on the radar for the top tier of Division I programs. For Claypool and assistant coach Nick French, she was the ideal recruit for a program that is part of Division I but won't receive its first fully funded scholarship until next season. She was a smart player who wanted the academic challenge the Patriot League offered and who wanted a chance to pitch.

And she had something that made her unique. Holy Cross wasn't going to get the pitcher with the best rise ball or the best changeup, but it could get just about the only pitcher with a knuckleball.

At first, the coaches envisioned it as an occasional off-speed pitch. Then they let her throw nothing but that pitch to confused batters for an entire inning of a fall exhibition game.

"The umpire is telling us he can read 'NCAA' on the ball," French said of the lack of rotation. "And the light bulb kind of went off and we said, 'What if we tried this?' "

To try it, they needed someone who could catch it. Rosenthal totaled just 31 at-bats her first three seasons, most of those late last season when she volunteered for duty behind the plate after injuries left the Crusaders short on options. When the knuckleballer from South Carolina arrived last fall, the coaches threw open the competition to catch a pitch that is almost as difficult to corral as hit.

And Rosenthal, who grew up a few blocks from Fenway Park in Boston's Back Bay, suddenly found a new appreciation for Doug Mirabelli, Wakefield's personal catcher who once received a police escort from the airport after the Red Sox were forced to reacquire him to handle the pitch.

"I wanted to be Jason Varitek when I was little," Rosenthal said. "I was obsessed. I had his chest protector; I wanted to be him. And when I started catching Gen, I kind of laugh now, because no one really appreciated Mirabelli."

So the physics major and the knuckleballer worked together through the fall and winter, finding time between classes to throw on their own. And when the season rolled around, the Crusaders turned loose their secret weapon.

In Durham's first college appearance, she gave up eight hits and five runs in less than four innings. And she hit a batter. The next day she gave up six hits and five runs in five innings, the defense committing five errors behind her. And she hit a batter.

It requires a lot of trust in physics to throw the ball that slowly. It also requires a short memory.

"You've got to trust your pitches no matter who you are as a pitcher, but the trust she has in that pitch, it makes all of her other pitches look amazing," Rosenthal said. "She has so much confidence in that pitch that when it gets hit, it's kind of like, 'Oops, don't worry about it.' This is her best pitch. It's her favorite thing to throw."

Durham led Holy Cross with a 3.27 ERA this season (take out that first weekend and her ERA was 3.04). Perhaps most remarkably, she began May ranked No. 16 in the nation in fewest walks per seven innings.

"We don't ask her to put it in a spot, but she's able to put it in a quadrant," French said. "We basically use those four boxes, and if I want it in that low-and-away box, she puts it somewhere in that box. And it's really incredible. She's really able to pitch with it."

Never more than that afternoon against Colgate. Her other pitches weren't working particularly well, but even with temperatures in the 40s, the knuckleball was moving. None of the first six outs left the infield, most of them popups to infielders. By the time she struck out the final batter of the fifth inning, she and everyone else were aware of what was unfolding, even if superstition demanded no one mention it.

"I was trying hard not to think about it, but obviously, it's in my mind," Durham said. "I tried to just focus on each pitch."

Holy Cross held just a 1-0 lead when Colgate came to bat in the seventh inning. With two outs, Mariel Schlaefer, ranked second in the Patriot League in home runs and slugging percentage, ran the count to 3-0. During one of the fall exhibition games, French went away from the knuckleball and called a fastball in a key moment.The opposing batter delivered a walk-off hit, and French said he learned a lesson. He had to let Durham win or lose with her pitch.

Rosenthal relayed the sign. A popup to third base ended the game.

And for a day at least, the knuckleball was the perfect pitch.