The Pittsburgh captain then sealed his team's first season sweep of its cross-state rival in 11 years with a pass that wasn't nearly as flashy but just as effective.
Pittsburgh pulled within three points of first-place Washington in the crowded Metropolitan Division and two points clear of Philadelphia after improving to 16-1-1 in its past 18 games at PPG Paints Arena.
''We did some good things, especially the second and third, created a lot and found a way to win,'' Crosby said of the Penguins, who have won a club-record 11 overtime games at home.
The Flyers tied it on Sean Couturier's goal with 43 seconds left in regulation, but the Penguins controlled the extra period. Rust ended it when his 13th goal of the season gave the Penguins their first sweep of Philadelphia since 2007 in what could be a playoff preview.
Crosby's second otherworldly goal in a week gave the Penguins the lead 17 seconds into the third period. The two-time MVP scored on an intentional double tap against Montreal last Wednesday. That one showcased his exquisite hand-eye coordination.
This one showcased his strength.
Crosby collected the puck high in the Philadelphia zone, used his left hand to keep Couturier at bay while using his right to dangle the puck before he skated to the left dot and ripped a wrist shot over Philadelphia defenseman Shayne Gostisbehere and Mrazek's glove.
''I was trying to skate into space, get open and just kind of watching him do his thing,'' Rust said. ''I'm not surprised. He is who he is for a reason.''
Couturier exacted a bit of revenge when he knotted it late to assure the Flyers of at least a point to pull them into a third-place tie with Columbus.
''It's a big point,'' Couturier said. ''We played a pretty good game overall. For sure, it's disappointing not coming out of here with two points, but we can build on this and maybe do a little better in little areas. Overall, I think we can build on this and keep going.''
Evgeni Malkin scored his 42nd goal for Pittsburgh, pulling within two of the NHL lead held by Washington's Alex Ovechkin. Patric Hornqvist and Derick Brassard also scored for Pittsburgh. Justin Schultz had three assists for the Penguins. Matt Murray finished with 41 saves.
Rookie Travis Sanheim picked up his second career goal for the Flyers. Brandon Manning and Jordan Weal also scored. Starting goaltender Alex Lyon was pulled early in the second period after giving up three goals on 11 shots. Mrazek made 19 saves, but couldn't get a glove on Rust's winner.
The erratic Flyers fell to 4-6-3 in March after going 10-1-2 in February and have struggled keeping their cross-state rivals in check this season. Pittsburgh scored five goals in all four season meetings, outscoring Philadelphia 20-12.
Considering how crowded the division standings are with two weeks to go in the regular season, a first-round playoff meeting isn't out of the question.
If it happens, it could match the wide-open postseason clash in which the clubs scored 56 goals in six games as Philadelphia pulled off an upset in 2012.
Pittsburgh's play in the defensive end isn't quite the hot mess it was six years ago, but the two-time defending Stanley Cup champions have struggled with consistency of late and had serious issues - particularly backchecking by the forwards - in keeping the puck out of their end at times.
The Penguins have allowed an average of 37.4 shots over their past six games, a number they understand needs to go down if they want to have a realistic shot at a three-peat.
''We have moments where I thought we were playing the game the right way,'' Penguins coach Mike Sullivan said. ''And then there were moments where we weren't. It's finding that consistency that's going to make us a stiffer team or a stingier team to play against.''
NOTES: The Flyers went 1 for 3 on the power play. Pittsburgh went 1 for 2. ... The Penguins scratched D Matt Hunwick and Fs Carter Rowney and Zach Aston-Reese. ... D Robert Hagg and Fs Taylor Leier and Dale Weise were healthy scratches for Philadelphia.
Flyers: Continue three-game road trip in Dallas on Tuesday. Philadelphia edged the Stars 2-1 on Dec. 16.
Penguins: Visit Detroit on Tuesday. The teams have split their first two meetings, each winning on home ice.
More NHL hockey: https://apnews.com/tag/NHLhockey
Copyright 2018 by AP. Any commercial use or distribution without the express written consent of AP is strictly prohibited.