The Edmonton Oilers twitter account broke the news:

Ralph Krueger speaking to the media. Hartikainen and Horcoff are in, Belanger (groin) to IR.

— Edmonton Oilers (@EdmontonOilers) March 10, 2013

Mark Fistric has joined the team but remains on IR for now. Potter back in the lineup, Peckham out and Smyth back at centre.

— Edmonton Oilers (@EdmontonOilers) March 10, 2013

Hemsky returns to the lineup tonight. Ben Eager is out.

— Edmonton Oilers (@EdmontonOilers) March 10, 2013

Belanger on the IR means Ryan Smyth moves back to centre - a position he's struggled to fill all season. Horcoff and Hartikainen should give the Oilers a huge lift in the possession game, especially with Ben Eager and Eric Belanger out.

The defense is still up in the air, however, with Potter in for Peckham and Ralph Krueger experimenting with the Justin Schultz - Ryan Whitney pairing against Nashville - there could be changes afoot.