Five observations from the Flyers' 5-1 loss to visiting Pittsburgh on Tuesday:

Not much electricity

A Flyers-Penguins matchup used to be the NHL's equivalent of the Yankees-Red Sox. Remember?

But Tuesday's game was a dud.

"The intensity wasn't there, not what it usually is," defenseman Andrew MacDonald said.

Oh, there was booing whenever Sidney Crosby touched the puck, and a few late-game chants, but for the most part, there was little electricity in the arena.

Yes, the Flyers' poor play over the last 30 minutes contributed mightily.

Penalty-killing woes

The calendar has changed to 2018, but the Flyers' penalty killing is as dreadful as it looked in 2017.

Pittsburgh was 2 for 2 on the power play. The Flyers began the night 29th out of 31 teams on the penalty kill with a 76.9 percent success rate. (The power play also struggled, as it went 0 for 4, though Shayne Gostisbehere hit the post with one shot.)

The PK has been even worse at home, killing just 70.2 percent of its penalties.

Better start, but …

The Flyers had a territorial edge and outshot Pittsburgh by 10-6 in the opening period. But they botched 2-on-1 and 3-on-2 breaks – failing even to get a shot off in both situations – and, as a result, failed to take the lead in the first.

The teams were scoreless after 20 minutes.

The Flyers have led after the first period just once in the last 19 games. That has to change if this team is going to make a playoff charge.

Metro blues

The Flyers are last in the Metropolitan Division. On merit.

They have just one win in six Metro games (1-1-4), and they missed a chance to slip ahead of the Penguins in the division.

"It was a good chance to kind of make a statement and get back in the standings," center Sean Couturier said. "We lost that chance, but at the same time, there are 40-some games left. Lots of hockey left."

Provorov watch

Ivan Provorov, the Flyers' best defenseman, blocked a shot with his left leg and limped around the locker room after the game before heading for X-rays. The Flyers will give an update Wednesday.

Provorov had a rough night and was on the ice for four Penguins goals – two at even strength, two on the power play.

On a night when Crosby and Evgeni Malkin didn't score goals, the Penguins' lower lines picked up the slack.