Usuthu this week called a press conference to slam reports that Nomvethe was inciting fans to rally against Johnson over his limited game-time.
The 40-year-old has made eight appearances this season, last featuring off the bench against Cape Town City on December 15.
Asked if he will field Nomvethe against Chippa United at King Zwelithini Stadium on Sunday (15h30), Johnson gave little away.
"Nomvethe plays every day. He's in the team every day. There's 30 players in the team every day," he said.
"There's big analysis that goes on behind the scenes, especially with the opposition we are playing against. We always try and take the best team that can win us the game when we are done with our analysis. So when I look at my team, Nomvethe can be in the team every day, my team.
"When I look at the opposition, then it is a different story. You can ask Nomvethe, the day we played Sundowns [in October] I told him, 'Nomvethe you're going to score today' and he said 'when?'. I said 'I'll show you today'.
"It's different courses for different horses on the day. If Nomvethe is honest, and if Mabhudi Khenyeza is honest, I said 'today, you'll score both of you' and they said 'why?'. I said ' because I know'.
"In all honesty, no disrespect to Nomvethe, he competes with everything. He competes in training, he does everything everybody else does. There's nothing wrong. The problem is it's different horses for different courses."