Gagne was drafted in the first round by the Flyers in 1998 and remained in Philadelphia until being traded this summer to Tampa for defenseman Matt Walker, who is currently sidelined with a hip/groin injury, and a fourth-round pick in the 2011 draft.
The 30-year-old winger recorded 259 goals and 524 points in 10 seasons with the Flyers and tonight marks Gagne's first game in Philly as a member of the opposition. Gagne has yet to register a point in two games with the Lightning.
"It'll be special," Gagne told CSNPhilly.com. "It will mean a lot. I spent 11 years there and 11 years in one life is a lot. And it's not just the 11 years. I started my career there. I was a rookie there. When I left home for the first time I went to Philly. ... Going back there is going to be weird. It's going to be hard."
Philadelphia will pay tribute to Gagne with a highlight video scheduled to play on the big screen during the first period of tonight's test.
Tampa Bay improved to 2-0 on the young season with an overtime victory in Montreal on Wednesday. Ryan Malone scored the game-winner with 51 seconds remaining in OT to lift the Lighting to a dramatic 4-3 win in the home opener at Bell Centre.
Steven Stamkos scored on the power play with less than two minutes to go in regulation to send the game to OT, while Brett Clark and Martin St. Louis also tallied for Tampa Bay. Stamkos, who tied for the league lead in goals last season, already has three tallies in 2010-11.
Mike Smith was in net in the opener and was credited with the win on Wednesday after stopping 24-of-27 shots.
With a minute left in the extra session, Malone battled to win the puck off a faceoff from the left circle. His initial shot was denied, as was a stuff by Dominic Moore, but the puck squirted back to Malone, who came around from the back of the net to put in the game-winner.
"On the winning goal I had to help on the faceoff. Then the puck came right in my range and I was able to whack it and I tried to whack it as hard as I could," recalled Malone.
The Lightning are playing the middle test of a three-game road trip and will cap the swing Saturday evening against the rival Florida Panthers.
The Flyers are coming off a win in their home opener on Monday and tonight will play the second test of a five-game homestand -- the club's longest residency of the season.
Philadelphia improved to 2-0-1 on the season with its 4-2 victory over the Avalanche. Jeff Carter scored a pair of goals, including the game-winner late in the third period, on a night that saw the Flyers raise their 2009-10 Eastern Conference champions banner to the rafters.
"It was a good feeling to see that banner go up, but that's also not the banner we want up there," Giroux said. "It was fun. The coach made a point to make sure that we'd get down to business after that and the guys were ready to go."
Sergei Bobrovsky, making his second career start, turned aside 25-of-27 shots for the Flyers to improve to 2-0 as an NHL goaltender. It's unclear if Brian Boucher or the undrafted 22-year-old rookie will get the start tonight.
The Flyers won all four meetings against Tampa last season and have taken five straight, six of seven and seven of the last nine encounters overall. The Bolts have also dropped three in a row and four of their last five games in Philly.