Game 2 of the best-of-7 series is at PPG Paints Arena on Wednesday (8 p.m. ET; NBCSN, CBC, SN, TVA Sports).
Sheary, who scored 23 goals in 61 regular-season games, was in such a funk that he was a healthy scratch for Games 5 and 6 of the Eastern Conference Final against the Ottawa Senators.
"I think I was making mistakes and getting down on myself," Sheary said. "I was trying things that I shouldn't have. If I stick to what I'm good at with my quickness and my speed and my compete level, that's when I'm at my best. I might have gotten away from that a bit for most of these playoffs.
"I was pretty disappointed with myself when I got sat out. I think I learned a lot from watching, got a little bit of a rest and I just tried to take it as a positive as much as I could, and I just tried to get back to my game."
Veteran center Matt Cullen was one teammate who urged Sheary not to get down on himself.
"He helped me a ton," Sheary said. "There's a lot of experience in this room, a lot of older guys that kind of told me I was a big part of this team, and that I helped us get here and not to get down on myself. Cullen] especially was one of those guys and I really took that to heart. I think a guy like that telling you that, as a younger guy, is pretty cool. I tried to use that as motivation."
When Sheary returned to the lineup for Game 7 against the Senators, he was reunited with Penguins captain Sidney Crosby and veteran forward Chris Kunitz.
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"I think you just get into a groove a little bit," Sheary said about fitting back in quickly. "When you're around the same players and on the line with the same players, you keep trying to do those things. Obviously myself and [Kunitz] have spent a long time alongside Sid, so we kind of know his tendencies and right now we're just meshing pretty well."
Sheary scored at 16:37 of the first period in Game 1 to give the Penguins a 2-0 lead, finishing off a pass from Kunitz by putting a shot into a wide-open net.
"Sid won a battle in the corner there and gave it up to [Kunitz] and I kind of saw an opening back door and I hoped that [Kunitz] saw me go that way and he did," he said. "He kind of made a bit of a no-look pass to me and it landed right on my tape. I had to just put it into an open net."
Sheary's relief was obvious, but after the victory he said nobody in the dressing room was fooling themselves about what's ahead in the Final.
"I think we know we have to play a lot better," Sheary said. "Maybe it's a good thing they haven't seen our best yet."
