While the first line will feature Michael Bunting and Mitch Marner on either side of John Tavares, lines 2 through 4 will have a much different look than even last game against the Philadelphia Flyers.
Per the Toronto Sun's Terry Koshan, the Leafs lines during warmups were:
Bunting - Tavares - Marner
Nylander - Kerfoot - Engvall
Mikheyev - Kampf - Blackwell
Clifford - Spezza - Simmonds
The biggest changes are obviously Colin Blackwell, Pierre Engvall and the all-veteran 4th line. Blackwell has been a staple as the Leafs' 4C since being acquired along with veteran Mark Giordano from Seattle. Blackwell did find himself on the second line on Tuesday against the Flyers, but now he'll slot in on what will be a high-energy, defensively responsible third line that could be a nightmare for the Bolts.
In Blackwell's usual spot at 4C, Jason Spezza comes back in, with Kyle Clifford drawing back into the lineup in the usual place of rookie Nick Abruzzese. Pierre Engvall will have a great opportunity to get a look in the top six on Thursday, along with Alex Kerfoot and William Nylander in a line of solid skaters who can all move the puck. Obviously, Nylander will be the trigger man on this line, but Engvall does have a very underrated shot.
With a win in Tampa, the Leafs could really put both the Bolts and the Bruins on the ropes. If the Buds win tonight, they'll be guaranteed to finish ahead of the Lightning, and the Bruins would essentially have to win out, with the Leafs losing each of their last 4 games in order for the B's to pass the Leafs.