VIERA, Fla. -- Nationals top prospect Lucas Giolito certainly looks the part of a Major League pitcher. At only 19 years old, he stands 6-foot-6 and weighs around 255 pounds after an offseason of putting on what he called "good weight."
After the start of his professional career was interrupted by Tommy John surgery, the right-hander is back on track toward bringing his imposing frame -- and 100-mph heat -- to a big league mound. Washington's first pick in the 2012 First-Year Player Draft returned to action late last season and now enters his first full year of pro ball.
"It's the best feeling in the world," Giolito said on Tuesday at the Nationals' Spring Training complex. "I'm ready to go. I'm ready to get going. It's just great that I was able to persevere through everything. I never had a setback."
The expectations are high for Giolito, who earned a signing bonus of nearly $3 million from the Nats. He is ranked as the No. 44 prospect in the game by MLB.com and No. 21 by Baseball America, despite having only 38 2/3 professional innings under his belt.
Two of those innings came in 2012, before his surgery. The rest came after he returned to action last July, finishing his season with three starts at short-season Class A Auburn, where he gave up one run on nine hits over 14 innings, racking up 14 strikeouts.
"It was unreal," Giolito said. "To be able to be out there and play on the team and compete, that's all I want to do."
Although the surgery delayed Giolito's development in some ways, it proved beneficial in others.
Rehab afforded Giolito an opportunity to strengthen his arm as well as his mind. He watched a lot of games, charting pitches and paying close attention to pitchers' sequencing and approach. And when he returned, he found that he was in possession of an improved changeup to complement a fastball that can reach triple digits and a hammer curveball.
"I developed a lot better feel for the changeup after the surgery," Giolito said. "It just comes out of the hand feeling a lot better and a lot different."
Now Giolito, feeling "fully healthy," is in line for a normal spring as he awaits his assignment, likely to one of Washington's full-season affiliates. He looks forward to gaining experience, pitching in front of bigger crowds and improving his command.
The California native is scheduled to throw a bullpen session on Wednesday, and Nationals manager Matt Williams is eager to get his first look.
"I've gotten great reports," Williams said. "I look forward to that tomorrow. I'm excited to go see him throw."
The Nationals have good experience in recent years with pitchers coming back from Tommy John surgery. Stephen Strasburg and Jordan Zimmermann both did, as did Taylor Jordan, whom Giolito has spoken with extensively about the rehab process.
With Giolito following the organization's recovery plan, there is a good chance he will operate under an innings limit this season, although he has not heard that yet. It's not something he is too worried about at this point.
"That's in the hands of the organization," Giolito said. "I believe there's some sort of limit, that's just how it is for all the guys that had Tommy John the year before. Whatever they want me to do, it's obviously for the best."
Andrew Simon is a reporter for MLB.com. Follow him on Twitter @AndrewSimonMLB.