Erat has an upper body injury while Hornqvist, a 30-goal scorer in 2009-10, has a lower body injury.
"Bergfors is coming into the lineup and he'll probably play with Sergei Kostitsyn," Predators coach Barry Trotz said of the line centered by Nick Spaling. "… I think he's a little bit like Sergei (in 2010-11), I think he had an OK camp, but it's just like last year, Sergei took a while to get used to how we play and I think Bergie had to catch up a little bit there.
"But he's really a pretty good detail guy, he's pretty competitive. What you notice about him, he's quick, but not fast. Sergei's more -- he can get from goal line to goal line a little quicker, but Bergie really darts in the short areas and he's got a really good release and that's sort of his game. With the way the game's played now, he should be pretty effective if we can get him into the offensive zone and get cycling around and making those short plays. He'll probably do a really good job there."
McGrattan, claimed on Tuesday off waivers from Anaheim, brings the known quality of grit. He has 395 penalty minutes in 182 career games. The Preds made room for him earlier in the week when they sent Zack Stortini to Milwaukee of the AHL.
Trotz said in terms of Nashville's defense that rookie Mattias Ekholm will be a game-time decision. Jack Hillen and Teemu Laakso, both of whom are minus-1, have formed Nashville's third pair. Ekholm was sick for the Preds' first two games last week.
Phoenix coach Dave Tippett did not announced any lineup changes after his morning skate.