With USC now through eight of its 15 spring practices, coach Lincoln Riley emphasized that the most important work is yet to come.

"We gotta have a great back half. Second half of spring, this is where average teams kind of start to fall off and great teams start to separate themselves," he said. "So we got a ton of work to do. I'm proud of what we've done halfway through, improvements that we would hope to make at this point I think have shown. ...

"But if we truly made that improvement it ought to show in that second half. In every aspect, whether it's something mental, whether it's something physical, whether it's effort, whether it's energy, understanding situations, every bit of it ought to be better in the second half."

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Riley underscored the effort he's seen while noting the physicality of the practices. He feels the players have been receptive to everything being ask of them as he and his staff look to remake the program into a contender again.

In terms of the evolution of practies, the Trojans are starting to add in situational work, including focusing on two-minute drills for the first time Thursday.

"I thought defensively we handled it well. We didn't handle it as well offensively. So a lot of work to be done there," he said.

Both Riley and defensive coordinator Alex Grinch talked about the scrimmage periods the team ran through during Tuesday's practice while noting that the tackling still has to improve -- which will come as no surprise to Trojans fans.

"We had times we tackled at a high level, times we didn't. Times we ran the ball at a high level and broke some tackles and didn't. When you sit in my position, something's going to be good, something's not going to be when you have competition," Riley said. "But it was good to see these guys kind of in a way take the training wheels off -- no coaches on the field, just officials out there. ... They feel the impact of their good plays, they feel the impact of their mistakes. So great simulation, a lot of good, positive work."

Grinch: "The typical thing, first time you get tackling in live situations, you see some opportunities where a ball-carrier should’ve been on the ground, and that’s at every level of the defense. So that’s something that’s expected, but it’s something we get the chance to coach off of and hopefully progress that way. You can only tackle so many times. And also being smart with guys out, you have to be smart that way. Overall, I think it’s been more on the plus side than the minus side. If you’re looking through rose-colored glasses, it’s pretty good. If you’re being honest, it’s not good enough to be where we want to be in the Pac-12. So we’ll show up again on Saturday and swing it back."

On to the rest of the notes from Thursday's practice ...

The latest player to get 'gold-plated' -- meaning earn the Trojans decal on their helmet -- was sophomore linebacker Raesjon Davis.

It was presented to him by former Trojans star Matt Leinart, who like Davis is a Mater Dei High School alum.

"It's honestly an honor. I feel like the first generation of gold plate is an honor, just to be able to get it and wear it, just to be able to earn it I feel like I've done a great job putting all my effort into earning this," Davis said.