SAN JOSE -- The San Jose Sharks had relied on their penalty kill all season.
It bailed them out of trouble time and time again.
But San Jose's six penalties proved costly in a 4-3 overtime loss to the Vegas Golden Knights in Game 3 of the Western Conference Second Round at SAP Center on Monday.
[WATCH: All Golden Knights vs. Sharks Game 3 highlights | Complete Golden Knights vs. Sharks series coverage]
Vegas leads the best-of-7 series 2-1. Game 4 is here Wednesday (10 p.m. ET; NBCSN, CBC, TVAS).
During the regular season, the Sharks were 84.8 percent on the penalty kill, second in the NHL behind the Los Angeles Kings (85 percent), and went 10-for-12 (83.3 percent) in the first round against the Anaheim Ducks.
However, on Monday, Vegas was given too many chances in Game 3 and found a few openings, going 2-for-6 on the power play.
"At the end of the day, it probably cost us," Sharks captain Joe Pavelski said. "They're a good team over there. They figured it out a little bit. Maybe a couple too many easy ones."
Said Sharks defenseman Brenden Dillon, "At the end of the day, that's kind of been our bread and butter this year. We've been really able to rely on that, and I think maybe we're taking that a little bit for granted and just got to get back to what makes us successful."
Less than a minute after Timo Meier scored to give the Sharks a 1-0 lead at 6:59 of the second period, Dillon committed a holding penalty that led to Golden Knights defenseman Colin Miller scoring on a one-timer on the power play to tie it 1-1 at 9:40.
Video: VGK@SJS, Gm3: Meier buries Tierney's pass for PPG
Later in the period, Golden Knights forward Jonathan Marchessault scored to make it 2-1 at 13:09 on another one-timer on the power play after Tomas Hertl was called for roughing at 12:47.
Reilly Smith scored 1:17 later to give the Golden Knights a 3-1 lead heading into the third period.
"They feel good about their game when they're making plays and that's when we took some undisciplined penalties," Sharks forward Logan Couture said.
San Jose had few answers for the Golden Knights top line of Smith, William Karlsson (who scored the game-winning goal at 8:17 in overtime) and Marchessault, which combined for seven points (three goals, four assists) in Game 3.
"They're quality players," Dillon said. "But I think for us, we've got a game plan, but I don't think we've completely executed it yet. We're kind of doing it in bits and pieces."
Sharks coach Peter DeBoer did not think the penalties were the only issue Monday, pointing out that they had dominant stretches in the first period but couldn't score, something they will need to fix ahead of Game 4.
"To come out of that first period 0-0, we need to find a way to get the lead," DeBoer said. "We're chasing the game the whole series here. Even when we have a quick start like tonight, [Golden Knights goaltender Marc-Andre Fleury] is shutting the door and finding the way to let them hang around until they can get something going, which is what happened.
"They got a power play in the second and got rolling a little bit. I think our game is in a good place. Just one of those games we're doing a lot of good stuff, but through the three games we're chasing the game every night. We've got to find a way to get out in front."
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