Simmonds was an instant fan favorite after coming over from the Los Angeles Kings in a trade for Mike Richards.
The 23-year-old Simmonds had career highs with 28 goals and 49 points.
"I don't feel pressure, but obviously I'm going to go out there, and I work as hard as I can every day whether it's on the ice or off the ice," Simmonds said. "I think I'm going to continue to progress as a player, and I'm going to do everything I can to help the Philadelphia Flyers win."
Simmonds has no regrets about missing out on the Kings' Stanley Cup win. Simmonds said he doesn't look back and is only focused on helping lead the Flyers to their first championship since 1975.
"I think it's been a great place for me," he said. "I signed this extension just hoping that we could bring a Stanley Cup to Philadelphia. I just want to be another piece of the puzzle. I think we have a great young core put in place. Obviously this is where I want to be for a long time."
Financial terms were not announced Thursday. Simmonds has one season left on his current contract. The new deal kicks in for the 2013-14 season.
Simmonds was involved in two preseason dust-ups - a man threw a banana at him and he had an altercation with former Rangers forward Sean Avery - and the fans showed their appreciation on opening night with a huge ovation.
He kept fans on his side and won over his teammates as one of the toughest players on the team.
Against Buffalo in February, Simmonds' mouth was busted open because of an errant puck in warmups. He needed 25 stitches in his upper and lower lips, then went out and scored two goals.
Simmonds hopes the ongoing labor dispute doesn't delay - or wipe out - the season. He hasn't yet made plans to play professionally overseas in case there is a lockout.
Simmonds believes his numbers would only get better over a full season.
"I'm not going to put numbers on it," he said. "But I need to get better as an all-around player and I'm definitely going to work toward that."
In Simmonds' first season, the Flyers had 264 goals and 103 points, but lost in the second round of the playoffs to New Jersey. On offense - with four forwards who topped 20 goals last season, including Simmonds - they should be fine. On defense, with the free-agency loss of Matt Carle, and injuries abound, Philadelphia could struggle.