NASHVILLE – First, Chris Johnson wants to get one thing straight – he's still fast, and he could still perform at a high level in the NFL if given the opportunity.

"I feel like if I trained the right way, I'd still be in the 4.2s," said the former Titans running back, who was clocked at a time of 4.24 at the NFL Combine in 2008.

And yes, the guy who became known simply as "CJ2K" insists he could still rack up yards in the NFL even after being out of the league for a year.

"I know for sure I'd get 1,000 yards if I laced them up," a smiling Johnson said on Tuesday night. "Shoot, that's not even a question. You put me in an offense where I'm the starting back, there's no way I wouldn't get 1,000 yards. I could still do it, but it's time to move on to the next situation."

The next situation for Johnson is to officially retire from the NFL – as a Titan.

Johnson, the electrifying back who played for the Titans from 2008-2013, will sign a one-day contract to retire from the NFL as a Titan on Wednesday in Nashville. Johnson announced his retirement from the league in November, but he said he wanted to go out as a Titan. Johnson played one season with the Jets (2014) and three seasons with the Cardinals (2015-17) after leaving Tennessee, a place he said felt like home after being drafted in the first round of the 2008 NFL Draft out of East Carolina.

Johnson traveled to Nashville on Tuesday, and he'll be at Saint Thomas Sports Park to sign his one-day contract on Wednesday morning, the day before the NFL Draft.

"Tennessee, that's the first organization that gave me a chance to make my dreams come true," Johnson said. "I have so many great memories in Tennessee and was able to do so many things with the Titans. It's an organization I always want to be considered a part of.

"I grew up in Tennessee. I went from being a kid to a grown man here. I might have grown up as a kid in (my hometown of) Orlando, but I was still a kid in Nashville when I got there. The team and the city, they've always shown me so much love. I have great memories from my days with the Titans, so many on the field and in the city. I've always loved Tennessee, and I always will because I've always felt so much love."

With 7,965 yards, Johnson departed Tennessee as the franchise's No. 3 all-time rusher behind Eddie George (10,009) and Earl Campbell (8,574). Over the six seasons, only Minnesota Vikings running back Adrian Peterson (8,774) had more rushing yards than Johnson.

Johnson's run with the Titans was highlighted by a 2009 season when he became just the sixth back in NFL history to eclipse the 2,000-yard mark in a season. Johnson was named the NFL's offensive player of the year that season, when he finished with 2,006 yards and set an NFL record with 2,509 yards from scrimmage.

"I know for sure I could still play," Johnson said. "Before I (announced my retirement), having talks with my agent about what we were going to do, I thought if I played one more year the only team I would come back and play for was Tennessee. I would love to have finished where I started. We had some discussions with the team, and they weren't looking to go in that direction. There were no hard feelings, and it didn't work out, so I decided to retire."

Johnson, who compiled 35 100-yard rushing games in six seasons with the Titans, including 24 games when he racked up 125 or more, said he loved every minute of his days in the NFL, with the Titans. He finished his NFL career with 9,651 rushing yards and 55 touchdowns. He also caught 307 passes for 2,255 yards and nine touchdowns.

Today, Johnson has twin boys, and a one-year-old daughter. He makes his home in Orlando. Johnson keeps busy, and this week in Nashville he'll launch "Johnson Performance Supplements" at an event on Wednesday night.

Johnson admittedly misses football, but he knows it's the right time to hang it up.

In his mind, his playing career went by as fast as his blazing speed on the field -- but that's a good thing.

"It definitely was a blast – it was fun," Johnson said with a smile. "I always tell people you can tell how much fun you have doing something by how fast it goes by. When stuff goes by real fast, it means you're having fun, and it seems like yesterday I got drafted and came in and met with Coach (Jeff) Fisher and coach (Mike) Heimerdinger. Now I look up and I'm done, I'm retired. But it was a great time.

"I'd be lying if I said I didn't miss it. I do miss it, but it's time to go on to the next chapter and see what's going to be next in my book."