SANTA CLARA — With only one preseason game under his belt since his ACL injury, 49ers linebacker Kwon Alexander appears to be back to normal.

“I feel the same, but I think I could get way better, it’s just my first game back,” Alexander said. “Got a lot of stuff to work on, but it’s going to get there.”

After watching Alexander’s performance in Kansas City, defensive coordinator Robert Saleh said the linebacker hasn’t skipped a beat when comparing him to film prior to his injury.

“If it’s different, I can’t tell,” Saleh said. “He made a couple of, he put a couple of O-Linemen on skates, one on a screen, one on the reverse early in the game and he just looked like he had good range, good tracking.

“He didn’t get tested too much vertically, but out in practice during training camp he has, and he hasn’t shown any limitations.”

Saleh was very complimentary of Alexander’s physical progress through his rehabilitation as well as his instincts and football knowledge.

“Kwon, from the first day of training camp until now, he is really coming along,” Saleh said. “His legs are getting underneath him. I love his style of football. He understands how to play football and how to get off blocks, how to play within space, his energy that he brings.

“He has, like I’ve said, tremendous football IQ. I’m excited about the direction he’s going in and he looks like he’s going to be ready to roll in terms of top-level performance by the time Week 1 rolls around.”

Alexander has been adapting to playing weak side (WILL) linebacker after playing in the middle (MIKE) during his four seasons with the Buccaneers. He has been working very closely with second-year linebacker Fred Warner, who will remain at the MIKE position for a second season.

“I’m trying to adjust to WILL from playing MIKE, it’s different,” Alexander said. “I’ve been playing middle since I’ve been in the NFL so it’s kind of different, but I can transfer it. I played it in college so it’s coming back to me.”

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Much has been said about Alexander bringing Warner out of his shell and developing him into much more vocal of a leader on the field. Alexander does take responsibility for that evolution and sees how it will reverberate throughout the entire defense.

“It’s been great, we feed off each other,” Alexander said. “Long as we do that, and have everybody feed off of us, we are going to make some big plays and do some big things around here.”