On the season, Johnson has 171 2/3 innings, which is the eighth-most in the National League.
Why the Marlins are cautious about their All-Star right-hander is because of the fact this is already the most innings he's thrown at the big league level. As a rookie in 2006, he rung up 157.
Johnson also underwent Tommy John surgery in August 2007, and this is his first full season since then. He made 14 starts, posting 87 1/3 innings in 2008.
"We're going to keep an eye on him," Gonzalez said. "He's thrown more innings than he's ever had before. We're going to keep an eye on those stressful innings."
Wednesday was an example of being careful. Johnson had thrown 92 pitches, and given up nine hits (which matched a season high) in six innings. Gonzalez considered bringing his ace out for the seventh, but reconsidered. Reliever Dan Meyer worked a scoreless seventh. Matt Lindstrom got through the eighth and Leo Nunez picked up his 16th save.
It wasn't a smooth six innings for Johnson, who dealt with base runners in every inning but once.
"We thought about running him back out there in the seventh inning. I think that's when you get into trouble," Gonzalez said, meaning pushing it. "We'll keep an eye on those first-and-second [situations] and nobody out, and if he gets out of the inning. Or that 19- 20-pitch inning. If we keep those under control, we should get through the rest of the season without any problems."
Physically, Johnson feels fine.
The way the schedule plays out, Johnson is lined up to make seven more starts, with his season wrapping up Oct. 3 at Philadelphia, the second-to-last game of the season.
"One of my goals at the beginning of the season was to get to 200 innings," said Johnson, who should easily surpass that total. "But when you're out there, that's the last thing you think about are your stats. You're out there doing what you can at the time."
More than upkeep of his arm or body, Johnson right now is trying to regain command of his slider and changeup.
Both pitches have been inconsistent of late. They were better on Wednesday, but still not overly sharp. On Aug. 20 at Houston, he didn't feel comfortable with either pitch. Johnson lost that game, and he was lifted after 4 1/3 innings.
"My slider isn't there right now. My changeup was better, but it comes and goes," Johnson said. "Maybe it's something really small mechanically I can change a little bit. Maybe I just need to stay back a little longer. We'll figure it out and we'll get to it."