With Xavier Rhodes “day by day” while recovering from a hamstring injury, Trae Waynes is trying to seize the day.

Waynes, Minnesota’s first-round draft pick in 2015, is practicing with the No. 1 defense at right cornerback and could start Sunday in the Vikings’ third preseason game, a noon kickoff against San Diego at U.S. Bank Stadium.

“I just want to keep getting better and better, and preseason’s the time to do it,” Waynes said. “The season’s right around the corner. I’m trying to make the most of the reps I get and (use) the experience and get some time under my belt.”

Waynes started the preseason opener Aug. 12 at Cincinnati in place of veteran left cornerback Terence Newman, who did not travel with the team because of an undisclosed injury. Waynes had four tackles (three solo) and knocked down a pass, but his positioning off the line of scrimmage allowed the Bengals to exploit his presence with short completions.

Rhodes was injured during the Aug. 18 exhibition game at Seattle and hasn’t practiced since, although he said his injury is “not too bad.” Newman returned for the Seattle game and is back at left corner.

Meanwhile, Waynes continues to work toward a starting role in the secondary. As a rookie last season, he played in 15 games, with one start, and made 30 tackles on defense and special teams, displaying his top-shelf talent while making a few mistakes.

“The game is completely different from the college level,” Waynes said. “I have the whole defense, the secondary, the coaches, to thank for helping me along with that. I mean, I’m a lot more comfortable than I was last year coming in and learning the system, so it’s allowed me to play faster.”

Reviewing Waynes’ up-and-down play in the Cincinnati game, head coach Mike Zimmer felt it was a matter of understanding the Vikings’ rules for cornerbacks and adjusting technique rather than a major issue.

“He’s got different rules,” Zimmer said. “There’s some rules. There’s also some times when I give him flexibility. One time, the guy just ran deep and on the next play he came up and he played off. So they have the flexibility to do that. But he was even too far off. He’s supposed to be at a certain depth.”

Waynes was able to use his speed and skill to make up for positioning mistakes at Michigan State, and some of those habits may be lingering, Zimmer added.

“When they’re covering receivers in college, the rules are so much different than they are in the NFL,” Zimmer said. “But then they get away with so many things where they can grab and hit after five yards and have all that stuff that doesn’t get caught, but here it does. That’s the stuff you really have to have corrected. Because of those rules, the techniques are totally different.”

Safety Harrison Smith said the middle of the preseason schedule is a good time for a young player like Waynes to work through those adjustments.

“Any time you can get extra reps, and get better, that’s what we’re doing right now,” Smith said. “It’s not as much game-planning, it’s more into fundamentals and those things, so the more reps you can get, the more it becomes second nature.”

Newman said Waynes has developed to the point where he and the veteran defensive backs “don’t have to do much” to bring him into the mix with Rhodes sidelined.

“I think it helps that Trae got some playing time last year and he’s comfortable,” Newman said. “We’ve just got to keep plugging along and make sure everybody who gets the call is playing hard. It’s the reason you have depth at the position.”

And, Newman joked, it’s not as if Rhodes has disappeared.

“He’s always out here, he’s got to see (practice) and watch film, he knows exactly what’s going on,” Newman said. “He doesn’t have a vacation; he’s still working.”