To the naked eye, it appears Philadelphia Eagles quarterback Carson Wentz is throwing the ball just as hard as he was pre-injury. Turns out, that's not the case: He's throwing it harder -- another encouraging sign as Wentz works toward completing his comeback from a torn ACL and LCL in his left knee.

The Eagles had Zebra Technologies' player tracking system installed at their practice facility in 2014. Tags on the players' shoulder pads generate biometric measurements, and a chip inside the ball calculates the velocity and spin rate of a quarterback's throws.

According to the data collected, Wentz's numbers have improved from last year to this year.

"Those are things we track actually with the footballs and things that we have. We can monitor that stuff. Velocity has been up, accuracy has been up. Those are the things he's been able to work on over the course of the year," coach Doug Pederson said.

"He got better last year, obviously, in games. To me it's all about eye placement, decision-making, accuracy, timing. It's all about the eyes and where you throw it and how you see it. That's one thing he's continued to get better at and work on. I do feel like now, because of the injury, he's focusing a little more on lower-body strength. It's really correlated to velocity and overall speed of the throw."

Added upper-body strength is a factor as well, quarterbacks coach Press Taylor noted.

"I think his velocity has been great. Obviously he had a lot of time to work on his upper body [while rehabbing the knee]. He's done a good job," Taylor said. "I think his arm endurance has been really good. He's been able to maintain those high-velocity throws throughout camp, throughout practice, which has been good to see."

Wentz is set to increase his workload by returning to team drills next week, he said. According to Pederson, Wentz will be re-evaluated after Thursday's preseason game against the New England Patriots to get a clearer sense of where he is physically and what he'll be able to do moving forward.

Wentz has not had to sit out any practices because of swelling and has looked more fluid in his motion as the summer has worn on. The outward signs, including the way he's spinning the ball, have been almost all positive.

The big hurdle standing between Wentz and game action is being medically cleared for contact. As far as getting that green light prior to the Sept. 6 regular-season opener against the Atlanta Falcons, Wentz believes "it's going to be close."

Wentz told reporters that he doesn't follow his tracking numbers too closely but rather goes off feel, and is happy with how his body has responded and the results he's seeing on the field.

"I feel good physically," he said. "My knee is feeling good, arm is feeling good. Come out [of training camp] feeling kind of ready to go a little bit."