The Boston Bruins have found a tremendous amount of success on the power play so far this season, and that continued in Thursday’s 4-3 shootout loss to the Tampa Bay Lightning.

Boston went 3-for-5 on the man advantage to continue its impressive numbers through the year’s first seven games. David Pastrnak extended his five-game point streak with two more goals and an assist Thursday, just one game after potting four against the Anaheim Ducks. He’s a major reason why that power play unit has been cooking of late.

But it’s not just Pastrnak. Boston’s top line has provided almost all offensive production for the Bruins to this point in the young campaign. The combination of Pastrnak, Patrice Bergeron and Brad Marchand has combined for 14 goals this season, while the other three lines have just three total goals. In fact, 14 of Boston’s last 17 goals have been scored by Pastrnak, Bergeron or Marchand, per NBC Sports Boston’s Joe Haggerty.

So yes, it’s nice to see the top trio finding the back of the net, but the Bruins know they’ll need to find more balance moving forward if they want to sustain their early-season success.

“The power play is going well right now, but I think we should focus on 5-on-5,” Pastrnak said, as seen on NESN’s postgame coverage. “Get a little more pucks to the net and find more pucks. … That’s when our skills can take over.”

Head coach Bruce Cassidy emphasized balance as well after Thursday’s loss, noting that once they achieve that goal, everything else likely will fall into place.

“Our record is fine, probably better than fine when you look at it on paper,” Cassidy told NESN’s Jack Edwards and Andy Brickley. “I think we’re relying too much on certain elements of the game — power play, goaltending, some of our top line. We need better balance in our entire game for 60 minutes. I think every team in this league is fighting to find their game for 60 minutes, but we have to find balance first and then we’ll string together 60 minutes. I think it’ll fall into place.”

Charlie McAvoy didn’t sound terribly concerned about the lack of balance, but noted it nonetheless. He’s confident, similar to his head coach, that they’ll be able to straighten things out moving forward.

“It’s just one of those things that kind of happens. It comes and goes,” McAvoy said of the Bruins top line carrying the scoring load. “I think once we break through, personally, I’m hoping to just keep pushing. … Those things come. They just do. There’s a ton of hockey left. We’ll find it.”

Here are some other notes from Thursday’s Bruins-Lightning game:

— Pastrnak had 41 goals last season, and he’s well on his way to another campaign with 40-plus. The winger is riding a five-game point streak, collecting eight goals and five assists over that span.

NESN

— Torey Krug feels his club can be playing smarter hockey.

“Our IQ’s a bit low right now,” Krug said, per The Boston Globe’s Matt Porter.

— Boston has collected at least one point in six of their first seven games to begin the 2019-20 season, all but wiping away the chance of a Stanley Cup (loss) hangover.

— The Bruins head to Toronto next for a Saturday-night matchup with the Toronto Maple Leafs at Scotiabank Arena.

Thumbnail photo via Greg M. Cooper/USA TODAY Sports Images