When it was finally completed, Chad Cordero twirled in the middle of the field and slammed his fist to his chest before striding toward catcher Brian Schneider for yet another round of congratulations. He will tease and he will taunt, and flirts with disaster as if it's the prettiest girl on the block.

Yet what Cordero, a 23-year-old right-hander for the Washington Nationals, has done over the first 21/2 months of this season -- culminating in an escape to make David Copperfield proud Wednesday night -- is establish himself as one of the most effective closers in the National League. He may not have a 96-mph fastball that gives hitters no chance. He may not stand 6 feet 5, able to physically intimidate the opposition.

"I'm not sure how I do it," he admitted recently. "I just try to go after hitters."

The results, though, are unmatched right now. His 21 saves are the most in the majors. In fact, entering Thursday's games -- the Nationals were off before beginning a three-game series at Texas on Friday -- no one else had more than 18. As impressive, his 1.06 ERA is the best among National League relievers. He hasn't blown a save since April 21, when the Atlanta Braves pushed across two runs on an errant throw from shortstop Cristian Guzman to conclude a slippery day at RFK Stadium.

But behind those stats are all the high-wire acts that have come to define how Cordero goes about saving games. There are, of course, the routine jobs, such as Tuesday night, when he entered with a three-run lead in the ninth and retired the Anaheim Angels in order. More frequently, though, come situations like the one he faced Wednesday night, when the Nationals carried a 1-0 lead into the bottom of the ninth, Cordero allowed a base hit, a walk and another hit -- and somehow escaped.

Someone asked him afterward if that was a "dream" scenario for a reliever, to face a bases-loaded situation, and then strike out Steve Finley on a hard pitch up and in, pop up Bengie Molina to shallow center field and finally strike out Dallas McPherson to end it.

"I don't know if it's a dream, but it feels good when you're able to get out of it like that, especially with no outs and having to go through the heart of their lineup," Cordero said. "To be able to get out of it, that's a great feeling for a reliever."

It is not, however, always a great feeling for his manager. Frank Robinson has joked this season about all the Tums and Rolaids that become necessary when Cordero enters a game. Indeed, in his 21 saves -- including the last 18 opportunities in a row -- he has allowed at least one runner 12 times, at least two runners on eight occasions.

"Obviously," Schneider said, "that's not the way you want to do it."

But there is something about Cordero that allows him to work his way out of such situations. There is no clear way to explain it, because while he looks to the world to be calm, he has admitted that his heart pounds beneath his chest.

"I just try not to worry about what happened, and just try to go out there and make pitches," he said Wednesday night. "Just try to act like there's nobody on. Just go out there and get an out somewhere."

Robinson, though, sees something subtle in those situations. During one such instance during the Nationals' recent homestand, Robinson and bench coach Eddie Rodriguez noticed that, with runners on, Cordero's fastball jumped from its normal 90 or 91 mph to 93. That, Robinson said, isn't typical. But Cordero does seem to improve with runners on base. Hitters have a .273 average against him with no one on and no outs, an average that drops to .182 with runners on, .132 with runners in scoring position and .053 -- 1 for 19 -- with runners in scoring position and two outs.

"What he has the ability to do is reach back and do, what we call, giving a little extra," Robinson said. "His ball doesn't have any more speed. It's usually right at 90, 91. But evidently, it has a little bit more movement on it, or he locates it a little better, when he gets in trouble. He seems to be able to get his fastball by hitters."

But not at an alarming rate. Cordero has 32 strikeouts in his 34 innings pitched, but he doesn't rank among the top 25 National League relievers, territory reserved for hard throwers such as San Diego's Rudy Seanez and Houston's Brad Lidge.

Still, Cordero has become the key to the Nationals' striking ability to win one-run games. They are 17-7 in such contests and have won nine of their last 10 decided by the narrowest of margins.

"One-run ballgames [are] the norm for this ballclub," Robinson said. "It's not the exception. They've gotten kind of toughened. They're tough to the situation, and they're excited in close ballgames."

None more than Cordero, who spends much of his time in the clubhouse quietly sitting at his locker, large headphones over his ears. Ask him how he's doing, he'll almost always respond, "Just chillin'."

Kind of like with no one out, a one run lead, and a runner on second. Just chillin'.