Hartnell was an unrestricted free agent after he had 24 points (13 goals, 11 assists) in 62 games with the Predators last season, and had four shots on goal in four games in the Stanley Cup Playoffs.
"Watching these (playoff) games, I still have a fire inside me to play again," Hartnell told Sportsnet on May 25. "My first priority, over the next couple of months, is to get ready [to return]. It wasn't the way I wanted to end it. I was scratched, came back and had some good games. If there's the right fit, I believe I can still be a presence, still be effective. If I didn't believe that, I would step away.
"I know I'm at the twilight … I don't know if I took it for granted, but after we lost Game 7 (to Winnipeg, in the Western Conference Second Round), I told the other guys, 'You don't know how many more chances you have. Don't let them fly by.' When you're in your mid-30s, you're 65 in the real world and out of the League."
Hartnell's wife, Katie, gave birth to their first child, Wesley Douglas, on May 21.
"Thanks again to my family, friends and all of the fans that cheered for me (and against) along the way," Hartnell said. "I'm looking forward to spending more time with my wife Katie and son Wesley. Cheers to the NHL, and the next phase of life!"