JUPITER, Fla. -- Gio Gonzalez has been as good as advertised.

The All-Star left-hander looked great in his Grapefruit League debut, throwing three scoreless innings. Gonzalez was outstanding again on Sunday with a group of family and friends cheering him on at Roger Dean Stadium.

"My parents, I had to tell them to turn it down a bit," Gonzalez said. "We're all grown men now. This isn't Khoury League anymore."

Gonzalez's family and friends drove about an hour and a half north from his hometown of Hialeah, Fla., to see him face the Cardinals. It is the closest to home that Gonzalez has ever pitched as a big leaguer and his cheering section made sure he knew they were there.

"They were definitely in the top of the stands," Gonzalez said. "I definitely heard that whole group of 20 over there.

"I think that was the main reason why I was looking forward to this trip. I took a quick power nap to find the energy to see my parents and friends and family. When you get that, it just makes you want to come alive a little bit."

Gonzalez did not disappoint his supporters as he tossed four shutout innings on Sunday before rain halted play after four innings with the Nats' ahead, 1-0. The 26-year-old allowed just two hits while striking out two Cardinals. He has not allowed a run yet this spring.

"I felt good," Gonzalez said. "There were a couple of things that I wanted to work on. Wilson [catcher Ramos] did a great job changing it up, working on the fastball curveball and changeup. I let my defense do the talking today and I'm grateful that we got some work in before the rain delay."

Gonzalez might have been most impressive in his final inning of work as he retired David Freese, Lance Berkman and Yadier Molina while a torrential downpour fell.

"It was tough," Gonzalez said. "It was almost at the point where I wanted to tell Molina, 'Here's a fastball. Hit it, please. I'm drenched over here.' That's a good hitting team. Even messing around like that, he could put a ball all over the field, so I kept the ball down and away."

Despite his success on Sunday, Gonzalez still feels he has plenty of things to improve on before Opening Day.

"I've still got more work to do," Gonzalez said. "We're moving forward and there are a lot of positive things that I could take from today and a couple of negative things. I definitely want to work on my timing and composure. This is Spring Training and that's what it's for. I'd rather get my stuff out of the way now and keep moving forward."

Gonzalez's success has him in the running to take the mound when the Nationals open the regular season against the Cubs on April 5.

"He's probably a candidate," manager Davey Johnson said. "He's probably the only one around here that's been an All-Star. With the exception of Chien-Ming [Wang], he's probably the only one that has been pushing 20 wins in the big leagues for a couple of years. Another guy with veteran experience is Edwin Jackson so we'll see. They haven't even gone through the rotation twice in the spring yet."

Gonzalez would be honored to be the Nationals' Opening Day starter but he knows the team has plenty of strong candidates for the job, including star right-hander Stephen Strasburg. Whether he starts against the Cubs on Opening Day or on another day, Gonzalez just wants to pitch.

"Everyone has earned their stripes to be up there and be in the top of the rotation," Gonzalez said. "Just give me the ball and I'm ready to go anywhere in that rotation. I just want to pitch. I don't look that far ahead. I just try to take it one step at a time. Stras is a great pitcher and so are [Jordan] Zimmermann, Edwin [Jackson], Chien-Ming and John [Lannan]. They all have a shot. I just want to keep under the radar and move forward."

If Gonzalez does earned the Opening Day start, he can count on hearing the same cheers from his parents at Wrigley Field. Those cheers will only get louder when he faces the Marlins in his hometown, and even more family and friends can attend.

But if Gonzalez continues to dominate in the summer like he has so far this spring, he will hear thousands of people cheering for him when he takes the mound at Nationals Park for the first time.