"Josh Johnson had just thrown seven scoreless innings to lead the Marlins to a 6-0 win over Pittsburgh on Tuesday at Sun Life Stadium.

He allowed two hits, struck out nine, had the winning hit, improved to 3-0 on the season and lowered his ERA to 1.00.

Johnson was asked if he could get any better.

"Yeah, why not? There is always room to improve," Johnson said.

That's bad news for the rest of the National League.

"He is going to take it to the next level," Marlins manager Edwin Rodriguez said.

Asked what that level might be, Rodriguez smiled and said, "I am not going to put any limitations on him."

Johnson has always had an overpowering fastball, but he is changing speeds more often and added of slow curveball that has made him a formidable force this season.

Johnson has pitched a total of 27 innings in his four starts and allowed three earned runs and five hits while striking out 27 and walking six.

Rodriguez said the curveball has turned into Johnson's key weapon.

"He is getting more confident with that pitch," Rodriguez said. "Slow curve, 95 mph fastball. It is hard to make contact."

One of Tuesday's strikeout victims was Pirates third baseman Pedro Alvarez, who got a look at Johnson's full arsenal in the second inning.

With the count 1-2, Alvarez fouled off a 93 mph fastball, fouled off an 87 mph slider, took a 79 mph curveball for a ball, then swung at a 88 mph slider and missed badly."