BOSTON — What a difference a few days can make.

Since losing to the Columbus Blue Jackets 3-0 on Tuesday, the Boston Bruins have called up Dan Vladar and Karson Kuhlman thanks to Tuukka Rask going on injured reserve with a concussion and Brett Ritchie getting waived.

So suffice to say the lineup might look a little different Thursday when the Bruins host the Pittsburgh Penguins at TD Garden in a clash between Eastern Conference heavyweights.

With Kuhlman up and Ritchie down, the second-year winger is expected to play on the third line. His center is to be determined, as David Krejci is a game-time decision with an upper-body injury. If Krejci is in, then Charlie Coyle will center the third line, per usual. If Krejci is out, Coyle bumps up to the second line and Par Lindholm will be the pivot on the third unit.

After getting benched for the Columbus game, Matt Grzelcyk is back in the lineup and expected to man his usual spot on the third pairing with John Moore.

Jaroslav Halak is going to get a taste of life as a “full-time” starter again for however long Rask is out. He’ll be in net against Pittsburgh, with Tristan Jarry likely to go for the Pens.

Here are the projected lineups for both teams:

BOSTON BRUINS (27-9-12)
Brad Marchand–Patrice Bergeron–David Pastrnak
Jake DeBrusk–Charlie Coyle–Anders Bjork
Danton Heinen–Par Lindholm–Karson Kuhlman
Joakim Nordstrom–Sean Kuraly–Chris Wagner

Zdeno Chara–Charlie McAvoy
Torey Krug–Brandon Carlo
John Moore–Matt Grzelcyk

Jaroslav Halak

PITTSBURGH PENGUINS (29-12-5)
Jared McCann–Sidney Crosby–Dominik Simon
Dominik Kahun–Evgeni Malkin–Bryan Rust
Alex Galcehnyuk–Andrew Agozzino–Patric Hornqvist
Zach Aston-Reese–Teddy Blueger–Brandon Tanev

Jack Johnson–Kris Letang
Marcus Pettersson–John Marino
Juuso Riikola–Chad Ruhwedel

Tristan Jarry

Thumbnail photo via Winslow Townson/USA TODAY Sports Images