Polak had found Steen wide open in the middle of the ice and hit him with a long clearing pass, sending in Steen alone on Carolina goalie Justin Peters. At that point, Polak knew what was coming.
''He didn't even shoot it and I was already celebrating because I know it is going in,'' Polak did.
It did, giving Steen a league-leading 17 goals and the Blues a 3-2 lead with 6:20 gone in the third period. T.J. Oshie added an empty net goal with less than a minute left to insure the Blues' fifth win in six games.
Steen, who also had an assist, extended his scoring streak to 13 games, the longest for a Blue since Pierre Turgeon had a 15-game streak in 1999-2000.
He credited Polak and Blues defenseman Ian Cole with making the play to send him on Peters.
''It was a good heads-up play to get the puck up,'' Steen said. ''They were in the middle of a change and I found a hole.''
Peters, who made 28 saves, said that one hurt.
''It stung getting scored on there in the third,'' Peters said. ''He came down and made a good shot.''
The Blues won despite giving up two short-handed goals on the same power play for the first time in more than 20 years. St. Louis last allowed that to happen on Oct. 8, 1992 against the then-Minnesota North Stars.
''Our power play has been good for us all year,'' Blues coach Ken Hitchcock said. ''We made a couple of mistakes on entries. We didn't get it deep and they took advantage of it.''
Hitchcock said that Steen's goal early in the third period was just what the team needed.
''Big-time player, big goal,'' Hitchcock said. ''We really needed that goal.''
''I thought our effort was there; our complete level was there,'' Staal said.
The Blues have scored first in their past 10 games, and did so again Saturday when Polak converted Chris Stewart's centering pass at 9:25 of the second period. Backes scored 2:11 later with a shot from a bad angle to make it 2-0.
It appeared that the Blues were in position to add to their lead when Carolina received a bench minor for too many men at 15:05 of the period.
Instead, the Hurricanes scored their first two short-handed goals of the season to tie the game.
First, Staal sneaked between the Blues defense for a breakaway and beat Elliott with a backhand at 15:37. Less than a minute later, Elliott mishandled the puck along the right boards. Riley Nash stole it and centered to Gerbe and he put it in the vacant net at 16:34.
NOTES: St. Louis, which had played the fewest games in the league coming into Saturday (17), will play seven more times before the end of the month starting Sunday in Washington. ... Carolina's Alexander Semin, who was hit with a hard check by Alex Pietrangelo in the first period, later left the game with what was announced as an upper body injury and did not return. ... Hitchcock earned his 618th win, moving him past Jacques Lemaire and into sole possession of ninth place on the wins list.