PITTSBURGH -- Maybe it was, as some of the San Jose Sharks suggested, a case of nerves or some rust from not having played a game in five days.
Or, perhaps, facing the speed and relentless pressure of the Pittsburgh Penguins for the first time required some time to adapt.
Whatever it was, the Sharks appeared overwhelmed for much of the first period of Game 1 of the Stanley Cup Final at Consol Energy Center on Monday. Although they played better in the second period, they could not sustain it in the third and lost 3-2 on Nick Bonino's goal with 2:33 remaining.
"We had some spurts here and there, but they played their game for longer stretches than we did tonight and that's what happens," Sharks coach Peter DeBoer said. "You don't deserve to win when you don't outplay the other team."
The Sharks need to figure out why before Game 2 of the best-of-7 series here on Wednesday (8 p.m. ET; NBCSN, CBC, TVA Sports).
Video: DeBoer speaks with media
From the drop of the puck, the Sharks looked a half-step slower. They were the faster team throughout their march to the first Cup Final in franchise history, defeating the Los Angeles Kings, Nashville Predators and St. Louis Blues on their way to the Western Conference title.
The Penguins presented a different challenge and the Sharks didn't have an answer early. The Penguins out-shot them 15-4 in the first period and jumped out to a 2-0 lead with goals 1:02 apart from Bryan Rust and Conor Sheary.
"They came out flying," Sharks center Logan Couture said. "It looked like we were stuck in mud."
Like the New York Rangers, Washington Capitals and Tampa Bay Lightning before them, the Sharks had trouble handling the Penguins' forecheck and making clean passes coming up the ice. That led to numerous turnovers, which the Penguins quickly turned into scoring chances.
Video: Marleau discusses hit, Sharks talk bad start
"It felt like we were giving it away, giving it right back to them," Couture said. "O-zone, D-zone, neutral zone especially. [We] just fed right into their transition. They had a lot of odd-man rushes because of plays that we made off of our sticks."
The Sharks returned to the locker room for the first intermission fortunate to be down 2-0. If not for goaltender Martin Jones, it could have been a lot worse.
"We got the 'Holy (expletive), we're here,' I think," defenseman Brent Burns said of the first period. "It was the first time you make it to the Stanley Cup Final. You dream about it for a long time. You probably used more energy the last couple days thinking about it than playing in a game. I sure felt it in the warm-up. You just get warm, not go too hard. I think we'll be better."
The Sharks were better in the second period. Getting a power play on Ian Cole''s hooking penalty 1:14 into the period helped. They converted with Tomas Hertl banking a shot in off the skate of Penguins defenseman Olli Maatta at 3:02 to pull within 2-1.
Video: SJS@PIT, Gm1: Marleau beats Murray, ties game in 2nd
Patrick Marleau tied it on a wraparound goal with 1:48 remaining in the second and the Sharks appeared to have momentum heading to the third.
"Just trying to get out of our end a little bit cleaner, a little bit better support all over the ice helped us out," Marleau said. "I think we were spread out in the first and turning pucks over, so we cleaned it up a little bit in the second and were better, but we've still got to clean it up."
As DeBoer noted, the Sharks had some spurts and chances in the third period, but the Penguins pressured them again into mistakes and peppered Jones with 18 more shots. On Bonino's winner, Burns lost his stick blocking an initial shot attempt by Kris Letang.
Video: SJS@PIT, Gm1: Bonino finishes Letang's pretty feed
Sharks defenseman Paul Martin then lost track of Bonino in front and allowed Letang's centering pass out of the right corner to get through. Bonino did the rest, lifting the puck past Jones' blocker.
"We didn't play our game in the first period. We stood around and watched," DeBoer said. "They're a fast team. They dictated play in the first. I thought when we played our game in the second, they had trouble with us. … I know we're going to get better. Our execution has got to get better. Part of it was some of the pressure they put on, but part of it was self-inflicted."
That was the prevailing opinion in the Sharks locker room. It was not what the Penguins did, but what the Sharks didn't do.
"They're fast guys and we didn't play a very good game," Hertl said. "We'll just take our lumps and look at the video and same as the three series before, just put the puck behind them and play in the [offensive] zone. That's our game. If we play the same as the second period, we can win. But if we're losing too many pucks in the neutral zone, we can't win against Pittsburgh."