LAKELAND, Fla. -- He's one of the biggest X factors in the National League East. And he has never thrown a pitch above Double-A.

But one of these days, Lucas Giolito is going to show up on a mound in Washington, D.C. And when he does, it's possible that everything about the NL East is going to change.

"If he's not up by June, something would have to go wrong," said one scout who has seen a lot of Keith Law's No. 1 pitching prospect in baseball. "You know what [Noah] Syndergaard and [Steven] Matz did for the Mets when they came up? This guy is in that same category."

We're talking, you understand, about a fellow who is only 21 years old, with just 253⅔ innings on his professional odometer. But already, ESPN, MLB Pipeline and Baseball Prospectus all rank Giolito as the No. 3 prospect in the whole sport. And over at Baseball America, he's "only" No. 5. So that tells you what the world thinks of him.

But the truth is, those rankings matter about as much to the Washington Nationals as the AP top 20 will matter Thursday on a March Madness hoop court near you.

What matters is that Lucas Giolito's time is almost here. And while he knows that time isn't Opening Day, he admits he has done a little dreaming. Hey, why wouldn't he?

"To be 21-22 years old and pitching in the big leagues and everything that comes with it, that's my dream since I was a little kid," Giolito said the other day, after punching out three hitters in a one-inning relief appearance. "I know every kid says that. It's kind of a cliché. But at the same time, it is my dream. It's where I want to be.

"So I'm trying to work hard and do everything I can to get to that point and contribute, especially in September, when there might be a playoff run, or in the playoffs. That would be amazing."

Well, "amazing" is one word for it. But if you asked the people who run his team to say publicly what they undoubtedly think privately, "amazing" probably isn't the word they'd pick. "Expected" might be more like it. For the moment, though, they're still choosing their words carefully.

"He's going to be an X factor for years to come. I can say that," Nationals general manager Mike Rizzo said. "As far as 2016, I don't know where he fits yet. We'll know a little bit more as spring training goes on. He's still new to the big-league scene. But he's a guy, hopefully, we can feel comfortable enough to count on sometime this year, if the opportunity arises or the need arises."

On paper, the Nationals are already overflowing with top-of-the-line starters, with Max Scherzer, Stephen Strasburg, Gio Gonzalez, Joe Ross and Tanner Roark all healthy and ready to rock. But let's think about it another way:

When isn't there a need for a 6-foot-6, 255-pound rocket-launcher who can blow up the radar guns with 98-mile-per-hour heat, has a man-eating swing-and-miss curve that he can drop out of the sky on any count and has an above average changeup that's getting better all the time?

Maybe the Nationals might not have a need for that right this minute. But when they start fantasizing about lining up Scherzer, Strasberg and Giolito in Games 1, 2 and 3 of a postseason series to be named later, it seems safe to believe they can work up an appetite for that tantalizing little scenario.

Rizzo used the word "electric" to describe Giolito's first appearance of the spring, back on March 4. And that'll work. All he did was strike out the side in the first inning he'd ever pitched on a big-league mound, on the way to two shutout innings against Miami.

Then, after allowing a wind-blown home run and a double to the first two hitters he faced in his second outing, last Wednesday against the Detroit Tigers, he took a deep breath, broke out his mesmerizing breaking ball and -- what else? -- whiffed the next three hitters on 12 pitches.

So already, he has scouts all over baseball shaking their heads and reaching deep into their reservoir of superlatives. Check out just a few of the glittering reviews we've heard:

"He could really be a superstar." ... "Reminds me of a young Chris Carpenter." ... "Has a great chance to pitch at the front end of a rotation for a long time."

We could keep going. But you get the picture. It's only a matter of time now. And the more the sport sees of Lucas Giolito, the more people wonder just how quickly his moment will arrive.

"Physically, he's really grown into the body that he has," Rizzo said. "And repertoire-wise, I think that's just about there. He's got some improving to do on his third pitch, the changeup. That's coming along. And the fastball is there. The curveball is there. The command is there."

So all that's left, the GM said, is "the little things that take a pitcher from being a prospect to ready for the big leagues." And on that front, "I think that he's close," Rizzo said. But those little things aren't all the Nationals are watching.

Also being watched closely? His innings, naturally.

Giolito says his road back from the 2012 Tommy John surgery is "old news now." But to the Nationals, it's a little more complicated than that.

From the day he was drafted in June of 2012, Giolito's elbow has been their central focus. He fell from the top of the draft and into their laps, at pick No. 16, because he was viewed, even coming out of high school, as just about a certain Tommy John surgery candidate. And sure enough, he made it through only two innings that August before driving his elbow into the ligament-replacement shop.

So even though the Nationals made that pick and went down that road with their eyes wide open, "you're taking a guy that you know you're losing for 14 to 16 months, and that's a little scary," Rizzo said.

"That's hard to explain to your ownership group," the GM went on. "I mean, you're giving a guy $2.8 million, and you're not going to hear his name for 16 months. But you try to convince them on the upside of what he can be, and what he was before the injury, and it's an easier sell."

Well, whatever he was selling, his owners were buying. And fortunately for everyone, it all has come true. But while Giolito has long been viewed as the Nationals' best pitching prospect since Strasburg, they've discovered that his quick trip to the Tommy John factory also came with a beautiful little side benefit.

"To be 21-22 years old and pitching in the big leagues and everything that comes with it, that's my dream since I was a little kid. I know every kid says that. It's kind of a cliché. But at the same time, it is my dream. It's where I want to be." Lucas Giolito

That surgery has allowed him to stay remarkably under the radar. Which isn't quite how it worked with Strasburg, in case you'd forgotten.

From pretty much the day Strasburg had his operation, it felt as if the entire industry was counting down the days until his return and counting up the innings he worked along the way. But none of that happens when a kid has Tommy John surgery at age 18, after two innings in the Gulf Coast League.

"You're free," Rizzo said, "to be as cautious or aggressive as you want to be, depending on the individual player and how he feels. There's no shutdown period, as there was with Stras. You don't have that decision or that drama. ... But it was the exact same program."

On one hand, Giolito has had zero setbacks along the road back. But on the other hand, the reason it's still an issue is that the Nationals have managed his innings carefully since his return -- from 36 in 2013, to 98 in 2014, to 117 last year. So if he's going to be a factor in the big leagues late this year, it means limiting his innings in the minor leagues early.

But Rizzo isn't about to broadcast how they'll go about that, saying only that "we'll monitor him carefully, as we do with all our guys coming off an injury."

So Giolito's presence in their camp this spring isn't designed to give him an opportunity to make this team. But it still has been "a fantastic experience," Giolito said, "to pick every brain and learn from the best."

And what happens next? Stay tuned, because even he isn't sure. Is he going to Double-A or Triple-A? Will he be starting or relieving? We'll all just have to sit back and find out, including Lucas Giolito.

"I couldn't tell you," he said. "There's a lot of business that goes into this. And a lot of development for me, obviously. I need to learn a lot, to be prepared, at the next level, to pitch in the big leagues. I feel like I want that opportunity to pitch at the highest level this year. And I'm ready and willing to take it whenever it comes. A lot of that is in the organization's hands, but also my hands.

"And I'm going to try to do everything I can," said America's top pitching prospect, "to prove I belong there."