Dontae Johnson stays upbeat after tough one

Four days after he was benched after struggling to cover Houston’s DeAndre Hopkins, 49ers cornerback Dontae Johnson focused on the positive: That nightmare is over.

“Of course, I was frustrated at the time, but that’s over with now,” Johnson said. “It’s on to Tennessee. That game’s in the past. My hat’s off to him. He’s a great player. A great competitor. It was a great challenge for me, but that game is over with and I’m ready for the next one.”

The next one is Sunday’s home date with the Titans, but it’s not clear if Johnson will retain his starting role after he was replaced by undrafted rookie Greg Mabin in a 26-16 win at Houston.

On Thursday, Johnson said he was practicing with the first-string defense. The situation is clouded because rookie Ahkello Witherspoon sustained a sprained knee against the Texans and has been limited in practice this week. After he was sidelined for four series, Johnson returned with 3:50 left after Witherspoon was hurt.

Defensive coordinator Robert Saleh insisted the plan was for Johnson to return eventually. He was replaced by Mabin after Hopkins had 10 catches for 144 yards and two touchdowns in the first 33 minutes. Saleh said he still had “faith” in Johnson. He also had three penalties while covering Hopkins.

“It was not a benching more than it was a breather,” Saleh said. “But Mabin is one of those guys who’s been working his tail off in practice. … So if you see him on the field, it’s not an indictment on what Dontae Johnson’s been doing as much as it is what Mabin’s been able to do in practice and giving him a chance to go put some tape on.”

Said Johnson: “That’s the nature of this business. If you have a good game, you have to be able to move on from it. If you have a bad game, you have to be able to move on from it. You’re only as good as your last game. I have another opportunity and that’s what I’m looking forward to.” Injury report: Right tackle Trent Brown (shoulder) missed another practice, increasing the likelihood Zane Beadles will replace him Sunday for a second straight game. Brown has missed two of the past three games with an injury he sustained in practice Nov. 23.

Seven players were listed as limited: tight end Garrett Celek (knee), safety Adrian Colbert (thumb, thigh), wide receiver Louis Murphy (illness), linebacker Mark Nzeocha (hamstring), safety Eric Reid (knee, rib), Mabin (calf ) and Witherspoon (knee).