"You'll have to ask me after the game because I don't know what to expect," said Girardi, who played 788 games with the Rangers before signing a two-year, $6 million contract with the Lightning as an unrestricted free agent July 1 after New York bought out the final three years of his contract June 14.
Girardi said he has spoken to former Rangers teammate Derek Stepan, who was traded to the Arizona Coyotes on June 23 and played his first game against New York on Oct. 26 at Madison Square Garden.
"He was telling me about the emotions," Girardi said. "I think that game will be different when I go back there, but [Thursday] is still going to be weird."
Girardi, who is fifth in Rangers history in games played by a defenseman, is not only with a new team this season, but he has a new role.
Girardi, who averaged 22:14 of ice time over his 11 seasons with the Rangers, is down to 16:29 through the first 13 games, playing with Braydon Coburn, 32, on the third pair.
"Definitely, it's kind of a different role," Girardi, 33, said. "They want me to still come in and play my game, but I'm not leaned upon to be the top guy. I'm paired with Coburn and we're still playing some hard minutes against top lines, [but] my job is to be really good defensively and if I can contribute on offense it's great.
"They wanted to shore up the defensive zone and we've done a pretty good job of that so far."
The role seems to be a fit for Girardi, who has a plus-6 rating and leads the Lightning (10-2-1) with 27 blocked shots.
Girardi, who has one assist this season, said being physical is a big part of the energy he was asked to bring to the defense and it fits with the kind of on-ice leader he likes to be. As for Girardi's mentality when it comes to blocking shots, he tries not to think about it.