Philip Humber was one pitch away from a perfect game and one pitch away from losing it.

The Safeco Field crowd was on its feet cheering against the home team, hoping for an out, wishing for this once-in-a-lifetime chance to witness history.

It was arguably the most compelling moment in the park since 2001.

The batter's box still was drenched in sunshine as Mariner pinch-hitter Brendan Ryan dug in for his second look at a 3-2 pitch.

In right field Alex Rios shifted nervously from foot to foot. Anxious catcher A.J. Pierzynski wiggled the sign.

A slider.

One pitch away from the Hall of Fame, one last pitch from becoming only the 21st pitcher in history to throw a perfect game, and Humber wasn't playing it safe.

"It takes a lot of confidence in your stuff to throw that pitch," Rios said. "And he had that confidence today."

A breaking ball with Cooperstown on the line. Pierzynski gave him the sign and Humber didn't shake it off.

"I'm not going to lie. I was being a little bit selfish. No matter what, I still wanted the no-hitter," Pierzynski said in the White Sox clubhouse after Humber had finished his 27-up, 27-down masterpiece. "If he walked him, he walked him."

On the previous pitch, Ryan, pinch-hitting for Munenori Kawasaki, had a good rip at Humber's 3-2 fastball. He was looking fastball again. But, as it had all day, Humber's slider twitched low and outside, as if it were sucked there by a vacuum. It would have been ball four, but it was too close for Ryan to resist.

Ryan checked his swing and home-plate umpire Brian Runge rung him up. The ball bounced away from Pierzynski. "Don't screw this up because if you do, you're going to be a goat for the rest of your life," Pierzynski told himself.

But with first baseman Paul Konerko waving at him to get the ball to first, Pierzynski completed the perfect game with a perfect throw.

"That was his best pitch all day, and we were going with his best pitch," Pierzynski said of that last slider. "And we were going down with it. I knew if we threw it close he was going to swing. In that situation, you (Ryan) want to get a hit. You don't want to walk. I knew that if he threw a good slider ... "

Angrily, Ryan threw down his batting helmet and argued that he had checked his swing. But the replay clearly showed he didn't.

"The closer they get (to the last out) the more borderline (pitches) might go his way," Ryan said, "because that's just the way things go. That's why I wanted to be aggressive. In that situation you have to be a little more aggressive with anything around the plate. That's just the way it's going to be.

"Anything that's kind of gray you have to at least get a piece of. It takes a lot of guts to make that pitch. But hats off to A.J. and, of course Humber."

White Sox players piled on top of Humber. The pile got so heavy, Humber said he yelled at fellow pitcher Jake Peavy to let him up so he could breathe.

It was an October moment in April.

"After the eighth inning, my hand was shaking," Pierzynski said. "You don't get that opportunity to be in that situation very often. I came into the clubhouse (after the eighth) and told Peavy, 'I'm nervous as crap.'

"I was more nervous for this than I was for the World Series, because there's no build-up for this. It just happens. You want it so bad for that guy on the mound. You want him to have that achievement forever and be remembered for that forever. It was a special thing that Phil did."

In this 4-0 win, Humber was all pop-ups and strikeouts and weak ground balls. The only ball that truly was hard hit was Dustin Ackley's line drive to right that Rios outran. This was Saturday afternoon surgery.

A game like this and a moment like that only can happen in baseball. This was a day that couldn't be anticipated. There was no feeling that this was a must-see moment in Seattle sports. No "SportsCenter" countdown.

Humber, 29, came into the game with only 11 big-league wins. But it became apparent after his second time through the Mariners' foundering lineup that he had an ornery slider that the M's lineup was helpless to hit.

Between the fourth and sixth innings, he threw only 20 pitches. He didn't run a three-ball count until Michael Saunders' leadoff at-bat in the ninth. Falling behind 3-0, Humber got Saunders on an explosive 3-2 slider.

"This was the biggest rush I've ever had in baseball, in my career," Rios said. "I was pretty nervous at the end of the game, but it was worth it."

Fans behind the White Sox's dugout, many of them wearing Mariners jerseys, gave Humber a standing ovation. A long, loud thank you for this chance to be part of Cooperstown.

It started out as an ordinary Saturday afternoon at the park. Philip Humber made it unforgettable.

Steve Kelley: 206-464-2176 or skelley@seattletimes.com