The Sabres host the Flyers on Wednesday night in the teams' first meeting since last season's memorable playoff battle.
Buffalo (6-4-0), which outscored opponents 20-10 in winning five of its first six, dropped to 1-3-0 over its last four games with Saturday's 3-2 loss to Florida.
"We have to wake up and do what it takes to play a system in this league," said Miller, who has a 3.04 goals-against average during his personal three-game skid. "You're not going to get away with making cute plays, you're not going to be able to carry the puck in ... you're not going to have that luxury. Too many mistakes, myself included. We're all accountable here."
The Sabres have been outscored 10-6 at even strength over their past four games.
"I said the other night it wasn't acceptable -- how we acted and how we played. It's not acceptable," Ruff told the Sabres' official website.
"You can go five or six minutes and play really well. Then we've done some things that have kind of hurt ourselves and we get on our heels. I don't think we've been the team we were that started the year, and we're just trying to get back to that."
A chance to avenge last season's loss in the Eastern Conference quarterfinals could have Buffalo more motivated. The Sabres held a 3-2 advantage over the Flyers (6-4-1) before surrendering 10 goals in the last two games and losing the series.
While Buffalo continues to falter, Philadelphia is coming off a 5-1 win over Carolina on Saturday behind a goal and three assists from Claude Giroux and a pair of goals from Jaromir Jagr.
The Flyers also got considerably better goaltending. Bryzgalov made 24 saves against the Hurricanes, looking more like the goalie who started 3-0-0 with a 1.67 GAA than the one who was 0-4-1 with a 4.62 GAA over his next five games.
"Sometimes, you just need to turn the switch on in your head and everything's changed," Bryzgalov said. "You have to fix your head, turn the switch on and go on."
With five goals and two assists over his last four games Jagr certainly appears to have found his form after going seven games without a goal upon returning to the NHL.
It's Giroux, though, who may draw the bulk of the Sabres' attention. The former first-round pick had a series-high nine points -- eight assists -- against Buffalo in the postseason.
Three of those assists came on the power play, which right now could use some work. After converting 11 of 40 (27.5 percent) chances through eight games, the Flyers are 1 for 14 over their last three.
"We're always working on it; we've worked on it for every pre-game skate," coach Peter Laviolette said. "I think you look at what you're doing and look at what you're generating and you hope to be opportunistic with the puck going in the net."
They'll have to make do in Buffalo without one of their most significant offensive weapons. Danny Briere, who has five power-play points this season and scored six goals against the Sabres in the playoffs, will miss his second straight game Tuesday with an upper-body injury.
That's good news for Miller, who posted two shutouts in the playoffs versus Philadelphia but gave up a combined 20 goals in the other five games.
Bryzgalov, meanwhile, went 0-3-0 with a 4.23 GAA during his last three meetings with Buffalo while with Phoenix.
Sabres left wing Ville Leino, who signed a six-year, $27 million contract in the offseason, faces his former team for the first time. He's recorded just one goal and one assist in 10 games.
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