Simon and Dea scored 76 seconds apart in the second period, and DeSmith made 34 saves for the Penguins in a 3-1 victory over the Carolina Hurricanes.
"They've been huge," Jake Geunztel said of his rookie teammates. "They're playing really well, and they have that excitement to be here. We have all been there -- and to see that, it's cool to be around, for sure."
Guentzel added a goal midway through the third and Crosby extended the NHL's longest active point streak to eight games for Pittsburgh, which has won six of eight.
Derek Ryan had the goal for Carolina, which has lost four of five and is 2-6-0 since beating the Penguins twice in a week spanning the New Year.
When Ryan gave the Hurricanes a short-lived lead 7:14 into the second period, there was reason to believe that might hold up because the Penguins had to that point scored just one goal in seven periods this season against Carolina and had been shut out for the prior 143:29 by veteran goalie Cam Ward.
But Simon -- playing in his 20th career game -- tied it just 49 seconds later when he skated down the right wing and flipped a deceptive wrist shot that perhaps deflected off defenseman Brett Pesce and beat Ward for his second of the season. Crosby was credited with an assist.
"It's great for our veteran guys," Penguins coach Mike Sullivan said about the rookies scoring. "It takes a little bit of pressure off the star guys that we rely on to generate offense night in and night out. The young guys scoring, that's such a boost of confidence for our guys."
Two shifts later, the Penguins' fourth line gave them the lead when Dea scored his first career goal in his fourth NHL game, finishing a nifty pass from Bryan Rust after skating open down the slot.
Dea had spent four full seasons in the minors before getting an NHL opportunity, and 4 1/2 before scoring his first goal. It set off an enthusiastic, fist-pumping celebration.
"It was special," Dea said. "I don't know what to say right now. It's a pretty amazing feeling. I dreamed about it since I was a little boy."
Guentzel slammed home a pretty feed from Phil Kessel at 11:02 of the third for his 15th of the season.
Starting for the third consecutive game, DeSmith has allowed four goals in that span and the Penguins are 2-1-0. No. 4 on the organizational depth chart when the season began, DeSmith is playing ahead of fellow rookie Tristan Jarry while starter Matt Murray mourns the death of his father this month.
"(The Penguins) started well, and then I thought we had a pushback in the second and really pushed in the third," Carolina coach Bill Peters said. "We couldn't find a way to get one by DeSmith."
Among DeSmith's better saves was a glove stop on Pesce, his former college teammate, on a wrist shot early in the first period. DeSmith also stopped Jordan Staal with his blocker late in the second and denied Lee Stempniak's chance from just outside the slot six minutes into the third.
"He was unreal," Simon said. "Today, again, he saved so many big chances. We can just say thanks to him because he has been great."
Penguins enforcer Ryan Reaves was a healthy scratch for the first time this season for Pittsburgh. ... The Penguins are 15-0-0 when leading after two periods. ... Crosby has 16 points, including 13 assists, during his streak.
Hurricanes: Thursday night at Montreal, which has earned at least one point in six of its past eight games.
Penguins: Continue a four-game homestand Thursday night against Minnesota, which is on a 4-0-1 streak.
More AP NHL: https://apnews.com/tag/NHLhockey