McAvoy has been sidelined 15 games with a sprained left knee ligament.
"Excitement for sure," McAvoy said. "Been a while, feels like it's been longer than it has. Four weeks of hard work, a lot of stuff behind the scenes to get back here. I feel really well and I'm excited to get back out there tonight.
"It just so happens that this is a very meaningful game and that makes it even more exciting for me to get back out there. I can't wait for tonight."
The Bruins and Lightning meet for the second time in six days. Last Thursday they played a heated game at TD Garden, a 4-2 Bruins win. Boston has won all three games between the teams this season.
Boston is in first place in the Eastern Conference, two points ahead of Tampa Bay.
McAvoy was skating with Zdeno Chara on Boston's top defensive pairing Tuesday morning.
Lightning captain Steven Stamkos is out of the game with a lower-body injury.