NASHVILLE, Tenn. —Curtis Grant was a Parade All-America performer in high school, and the starting middle linebacker for a national championship team in college at Ohio State.

So when he found himself out of football, it was a shock to his system.

Grant, signed by the Titans in April, spent part of the time delivering packages on one of those brown UPS trucks. He also trained with an unlikely partner as he waited for another chance.

"It was a hard time,'' Grant admits. "You go from having a whole bunch of accolades and being part of a team, to really having nothing. It is even harder when you are (an undrafted) free agent instead of a drafted guy. But it makes you respect everything you do and it makes you want to work harder and appreciate it more.

"But I have the taste back now, knowing I can do it. And I don't have that "give up" mindset. I just want to keep going."

The Titans discovered Grant while working out draft-eligible players like Joey Bosa, Eli Apple and others on the Ohio State campus leading to the NFL Draft, and he's made himself known in Tennessee.

He leads the Titans with eight tackles through two preseason games. On Saturday, Grant ran down Panthers quarterback Cam Newton, stopping him short of a first down. The play got coaches and teammates riled up on the sideline.

"He made a hell of a play on Cam,'' Titans defensive coordinator Dick LeBeau said of Grant. "Cam is not used to having a guy do him like that. That was pretty cool. He has done a good job."

Coach Mike Mularkey called Grant "a pleasant surprise."

"We were (at Ohio State) working out their draft class basically, and he came out and worked out, and he had a great workout,'' Mularkey said. "So (General Manager) Jon Robinson and I said, 'This guy has shown something in a workout, let's sign him. What do we have to lose?' This guy has stepped up and done a lot of good things. It was a good signing."

Grant's now hoping to stick with the Titans, something he wasn't able to do at previous stops with the Chargers and Falcons.

After being passed over in the 2015 NFL Draft following a stellar career at Ohio State, Grant signed with the Chargers as an undrafted free agent last May. But he was released by the Chargers following the team's third preseason game last year.

Grant was out of football until December, when he was signed by the Falcons. He spent the last three weeks of last season on the team's practice squad but then found himself out of a job again.

In between NFL jobs, Grant went back to school. He spent time last year working for UPS, delivering packages just outside of Richmond, Virginia. He was living with his mother.

"Probably delivered about 1,500 packages a day,'' Grant said. "It was a workout, going from house to house, up hills. But it wasn't exactly what I wanted to be doing."

He wanted to be back on the football field, of course.

Grant stayed in shape by training with his 55-year-old aunt, Cheryl, who was trying to lose weight.

"We trained together every day, but I was also basically trying to get her confidence up. She wanted to get into better shape,'' Grant said "I invited her along, and she wanted to change her life. I took it as a challenge to help, and in the meantime make myself a better person.

"I would push her, but she actually helped me push me, too. Because the days I didn't feel like working out, I'd look at her and hold myself accountable. Because I'd look at her and I was like, "I know I can't quit on her."

Fast-forward to today.

Grant said his aunt is down 45-50 pounds, and she was in attendance at Nissan Stadium along with other family members to cheer on her nephew.

"She's doing great,'' Grant said.

Grant's in a fight to make the team's roster.

He's doing everything he can to stick. He wants to deliver for the Titans

"My new motto is: Positive vibes only,'' Grant said. "I like to be in positivity at all times. I like to think when I go into something, the outcome is going to be great. If you go in with a negative mindset, that is a form of fear. If you go into something with a form of fear, it won't help you succeed. It will force you to make mistakes.

"I just want to keep a positive mindset and give it my all, and hopefully it works out."