VIERA, Fla., Feb. 23 -- Every year at every baseball training site from Florida to Arizona, someone appears as a potential spring fling, a dance partner who instantly merits a second or third date. He dazzles at introductions, teases with his talent, makes the men who run baseball clubs wonder if he could be part of a long-term relationship.

Such is the case with one Emiliano Fruto, or, as he was known to his former teammates in Seattle, "Cabeza Grande," what with his 7 3/8 -inch hat that only partially covers a massive forehead. But here, at the Washington Nationals' camp, it isn't Fruto's head or his legendary ability to juggle a soccer ball or the fact that he can outrun most of his fellow pitchers in a sprint that has folks intrigued. It is simply what caught the eye of Bob Boone, the club's director of player development, during a scouting trip last year.

"He's a baby," Boone said, "with a big arm."

Which is exactly what makes him so enticing, a 22-year-old who blazes into spring as an unknown acquired in a trade for a veteran, second baseman Jose Vidro. If there is one part of the Nationals that is all but set, it is the bullpen, anchored by closer Chad Cordero, who will be accompanied by set-up men Luis Ayala, Jon Rauch and Ryan Wagner and, ideally, a pair of lefties -- likely Ray King and Micah Bowie. That leaves one more spot. And before a pitch has been thrown in competition, a week before games begin, Fruto is creating early buzz that he might be able to win it.

"Nasty," catcher Brian Schneider said. Catchers who have caught him and hitters who have faced him talk about his change-up, which is already major league ready, not to mention the zip on his fastball and the arc of his curve, a three-pitch arsenal that suggests he could, if needed, be converted to a starter.

These, though, are the cautionary tales of February, post-Valentine's Day romances sparked by the hope -- warranted or not -- that naturally springs up at this time of year. General Manager Jim Bowden leaned against the batting cage Friday morning as Fruto reared back and threw pitches to a slew of hitters in live batting practice. Yes, Bowden reiterated that he was happy to get Fruto as part of the December trade for Vidro because of the potential in his three pitches and his sturdy, 6-foot-3 body.

"As he continues to improve his command in the strike zone," Bowden said, "he's got a chance to be a quality reliever, or even a starting pitcher, down the road."

The operative word there: chance. During the next week, as the pitchers continue to refine their repertoires and prepare for live action, Bowden will make the occasional trek from his office down the road at Space Coast Stadium to the club's minor league complex, where workouts are held. He will watch the three dozen pitchers he and Manager Manny Acta and the coaching staff are considering for the final trek north. He will make mental notes, have moments of excitement, extrapolate a performance in the bullpen into what it might mean during a game. And then he will put all that to the side, because it is essentially meaningless.

"This time of year, all you can measure is deliveries and stuff," Bowden said. "You don't know how a guy pitches, how he reacts in a game. Anybody who thinks they can evaluate a pitcher this time of year is just being ridiculous."

The evaluation for the Nationals, though, began when Fruto was in Seattle's farm system, where he had occasional lapses in focus that led the organization to move him from the rotation to the bullpen. "That's probably the only thing he had trouble with, with us," said Mariners closer J.J. Putz. "But when he was locked in, he had devastating stuff."

Fruto, signed by the Mariners out of his home town of Bolivar, Colombia, when he was 16, arrived in the United States for the first time without his family, and said he struggled to adjust.

"I [had] never been away from my family," he said Friday. "It was hard, very hard."

By 2005, though, he was at Class AA San Antonio, where he had his breakout season as a pro, posting a 2.56 ERA in 40 appearances, striking out 63 batters in 66 2/3 innings. Last May 14, he made his major league debut.

"I was nervous," he said. It didn't show. Seattle Manager Mike Hargrove brought Fruto in with one out in the sixth inning of a game the Mariners led, 7-4. Hargrove never went back to the mound. Fruto closed out the win, allowing one hit in 3 2/3 innings.

"When he threw strikes," Hargrove said, "he was impressive."

But he didn't always throw strikes. In compiling a 5.50 ERA in four major league stints last season, he walked 24 men in 36 innings. In 15 of his 23 outings, he walked at least one man. In six of those, he walked more than that.

There are, of course, no umpires during bullpen sessions on the back fields here, no one to say whether a pitch was on the black or a hair off the plate, making it that much easier to get excited. Asked about Fruto's early performances, Acta said, "I'm impressed." Still, coaches and front-office members say he must improve his location, his consistency. There is work to do before this spring fling becomes a true relationship. The spark, though, is there.

"He's right there," Boone said, "right on the cusp of helping us."

Staff writer Dave Sheinin contributed to this report from Peoria, Ariz.