The Sharks' penalty-killing is costing them big-time in their first-round series with the Blues. San Jose allowed three power-play goals on four chances in their 4-3 Game loss, and their efforts on the penalty kill have been a major problem in the postseason as they've allowed goals in each of the three games. If the Sharks want to extend this series, their best bet is to stay out of the box -- they also had the second-worst penalty-kill percentage in the league during the regular season. "It affects your confidence, your ability to keep going," coach Todd McLellan said. "It changes the way you play the game. Sometimes you're not as aggressive as you should be because you're afraid to go to the box. There's no doubt about it. We have to fix it."