Nationals right-hander Stephen Strasburg was scratched from Thursday’s start but is scheduled to take the mound Saturday.

When an injury of any kind is linked to Stephen Strasburg, there’s a reason for caution, as far as the Nationals are concerned.

After already missing a start against the Mets last Friday due to tightness in his right forearm, Strasburg was still experiencing the same issue and was scratched from Thursday’s start against the Marlins.

“He wanted to pitch [Thursday] and I said, ‘No way, I got guys on full rest. I’ll pitch [Gio Gonzalez and Jordan Zimmermann] and you can be in the lineup for Saturday,’” Johnson said. “It was my decision.”

The Nationals have played it safe with Strasburg since selecting him with the first overall pick in the 2009 MLB draft. About 2½ months after making his big league debut in 2010, Strasburg tore his ulnar collateral ligament and needed Tommy John surgery.

He saw little time in 2011 and had his season cut short by an innings limit in 2012.

This year, Strasburg has seen his workload increase, but a few nagging injuries have popped up along the way. He’s dealt with similar soreness in his right forearm at times this year, as well as a lat strain that led to a brief stint on the disabled list.

Strasburg said he’s been checked out by the team doctors and that his arm is structurally sound. Therefore, he can’t figure out why the tightness won’t go away.

“It’s like a real strong cramp,” Strasburg said. “I think it would put us in a bind if I went out there and felt it. We’d definitely be down some pitchers.”

When Strasburg’s arm does warm up, he said, he’s generally pain-free. The process of getting his arm to that point is what kept him out of Thursday’s game.

“In my book, I don’t want to have anything bothering you the day before you pitch,” Johnson said.

For the season, Strasburg is 7-9 with a .296 ERA in 28 starts. Johnson was confident that Strasburg would be ready by Saturday’s game, as was Strasburg himself.

“I wouldn’t say I’m too concerned because when I get nice and loose I feel 100 percent,” Strasburg said.