PLAYOFF SERIES: Western Conference quarterfinals; Sharks lead 3-1.
A 3-1 series lead is far from safe in the NHL playoffs.

The St. Louis Blues know it, but their circumstances remain daunting as they try to stave off elimination in Game 5 against a confident San Jose Sharks team.

St. Louis, coming off a 4-3 loss in Game 4 on Tuesday, has seen firsthand what it takes to overcome that deficit.

The Blues blew a 3-1 lead in the first round against the Vancouver Canucks last spring. St. Louis, though, has rallied from a 3-1 deficit only twice in 12 tries -- the last time in 1999.

Plus, the Blues are facing a team that is receiving contributions from every forward line.

After a strong performance in San Jose's 4-1 loss in Game 3 on Monday, Alexander Korolyuk helped the Sharks bounce back and regain control of the series. Korolyuk, who scored 19 goals during the regular season, got his first two goals of the postseason in Tuesday's victory.

Among Korolyuk's Game 3 contributions was a first-period hip check that knocked Blues forward Ryan Johnson out of that contest, as well as Game 4. Korolyuk moved up to the first line toward the end of Game 3.

``It's just kind of a message to the rest of the team that if you do the little things well and play like a warrior, you'll end up on top,'' Sharks coach Ron Wilson said.

Unsung Scott Thornton also got his first two goals of the playoffs for San Jose, the No. 2 seed in the Western Conference.

Thornton had only six goals, a career high, and 21 points during the regular season. He had never scored in 22 career postseason games before beating Osgood in the first and second periods.

Sharks center Alyn McCauley missed his third straight game Tuesday with an apparent shoulder injury. His status for Thursday is uncertain.

After losing the first two games, the Blues outshot the Sharks 25-8 in the first two periods en route to a 4-1 victory in Game 3. The Sharks, though, regained control of the series in the second period Tuesday, spending most of the 20 minutes in the Blues' end and outshooting them 12-5 while scoring twice to break a 1-1 tie.

``It was a frustrating period,'' Blues forward Doug Weight said. ``It was there to be won. A couple of lapses and we paid for them.''

The Blues scored twice in the third period, but couldn't overcome a pair of two-goal deficits.

Ineffectiveness on the power play helped put St. Louis in a hole. The Sharks' penalty killers made it difficult for the Blues to set up with the man advantage, running their streak to 18 straight kills before Doug Weight's scored with 4:53 left. That cut San Jose's lead to 4-3.

``Our special teams have done the job all year and we have to continue to do it,'' Sharks center Mike Ricci said. ``Our power play was huge tonight and the PKs were pretty tough also.''

Mike Danton and Pavol Demitra also scored for the Blues. Demitra's goal was his first of the series, and Danton scored for the first time since Feb. 10 to end a 17-game drought.

HOW THEY GOT HERE: Blues - 91 points; 7th seed. Sharks - 104 points; 2nd seed.

PLAYOFF TEAM LEADERS: Blues - Mike Sillinger, 3 goals and 4 points; Keith Tkachuk, Christian Backman and Petr Cajanek, 2 assists; Chris Pronger, 16 PIM. Sharks - Patrick Marleau, 3 goals; Vincent Damphousse, 3 assists; four with 3 points; four with 6 PIM.

PLAYOFF SPECIAL TEAMS: Blues - Power play: 5.3 percent (1 for 19). Penalty killing: 88.9 percent (24 for 27). Sharks - Power play: 11.1 percent (3 for 27). Penalty killing: 94.7 percent (18 for 19).

GOALTENDERS: Blues - Chris Osgood (1-3, 2.36 GAA); Reinhard Davis (0-0, 0.00). Sharks - Evgeni Nabokov (3-1, 1, 1.69); Vesa Toskala (no appearances).