Dylan Holloway had two goals and an assist, Logan Mailloux had a goal and an assist, while Robert Thomas and Jake Neighbours each tallied two assists for the Blues (36-33-12), who have won three straight, including a 6-3 win against the Minnesota Wild on Monday. Jordan Binnington made 18 saves and had an assist.
Avery Hayes scored twice, Anthony Mantha had a goal and an assist, and Kevin Hayes had two assists for the Penguins (41-25-16), who closed out the season with three straight losses. Stuart Skinner made 17 saves on 21 shots through two periods before being replaced for the third period by Arturs Silovs, who made seven saves on nine shots.
The Penguins, who will face the Philadelphia Flyers in the Eastern Conference First Round, rested several veteran players, including forwards Sidney Crosby, Evgeni Malkin, Rickard Rakell, Bryan Rust and Egor Chinakhov, as well as defensemen Kris Letang, Erik Karlsson, Samuel Girard and Parker Wotherspoon.
Pittsburgh went up 3-0 in the first period, starting with a goal from Rutger McGroarty that put the Penguins on the board 1-0 at 10:14. He got a quick wrist shot off from the left face-off circle in the offensive zone after Kevin Hayes won the draw.
Avery Hayes made it 2-0 at 16:40 on a breakaway after Mailloux fumbled the puck at his offensive zone blue line, putting a wrist shot past Binnington glove side.
Mantha made it 3-0 at 17:23 off a turnover by Blues forward Alexey Toropchenko at the blue line. Kevin Hayes found Mantha in the left circle and he put a wrist shot to the short side.
Snuggerud ended the Penguins' run and made it 3-1 at 18:44, scoring from the slot off a Thomas pass. The score marks Snuggerud's 20th NHL goal in his rookie season.
Elmer Soderblom made it 4-1 at 2:58 of the second period when he used his body to power past Blues defenseman Tyler Tucker and spun around in front before slamming a wrist shot past Binnington.
Oskar Sundqvist’s rebound goal at 4:51 made it 4-2 and kicked off the five-goal comeback effort for St. Louis. He found the open net to score on Toropchenko's rebound with Skinner out of position. Toropchenko took the initial shot on a 2-on-1 breakout after getting the stretch pass from Philip Broberg.
Mailloux’s wrist shot from the high slot made it 4-3 at 10:37, and Snuggerud’s second goal of the game came on the power play at 15:49, when he tapped in a Neighbours' cross-crease pass to tie it 4-4.
The Blues scored twice in 44 seconds early in the third period starting with Holloway, whose wrist shot off a pass from Snuggerud in the slot made it 5-4 at 4:11. Pavel Buchnevich pushed the Blues' lead to 6-4 at 4:55 with a top shelf wrist shot over Silovs' blocker on a breakaway thanks to a stretch pass from Jordan Kyrou.
Avery Hayes cut it to 6-5 with his second goal at 12:20 when he followed up his own shot and banked the rebound off Binnington's left skate and in, and Holloway capped the comeback with an empty-net goal at 18:17 for the 7-5 final.
