On July 1, 2009, Boucher agreed to a two-year contract with the Philadelphia Flyers to be the steady, veteran backup to the starting goaltender Ray Emery.
However, when Emery incurred an injury midway through the season, Boucher was thrust into the spotlight with mediocre results.
A hand injury soon pushed Boucher to the sideline, and he was replaced by third-string goaltender Michael Leighton.
Leighton excelled in Boucher's absence, and once healthy, Boucher found himself backing-up Leighton.
Upon the return of Emery, Boucher was further demoted to the press box, with Leighton now the backup.
Emery soon re-injured himself, giving Boucher a chance to back-up Leighton, who once again was playing well.
Near the end of the season, with only 13 games left, Leighton went down with a high-ankle sprain, and Boucher was back into the spotlight for the Flyers once again.
After a 2–1 shootout victory in the final game of the season against the New York Rangers, Boucher and the Flyers advanced to the playoffs.

In the 2010 playoffs, Boucher defeated Martin Brodeur and the New Jersey Devils in the first round four games to one.
The national media remarked he was the surprise of the playoffs after the first round with his outstanding play in net.
The Flyers defeated the Boston Bruins in the second round by overcoming a three-game deficit, but Boucher was injured in Game 5 of that series with knee injuries.
Boucher returned from his injuries to serve as a backup to Leighton in Game 1 of the Stanley Cup Finals against the Chicago Blackhawks.
He saw game action in Game 1 and Game 5 in relief of Leighton, but the Flyers lost in six games to the Blackhawks.

In the 2010–11 season, Boucher split time in goal with standout rookie Sergei Bobrovsky after Leighton was demoted to the AHL, in part for hiding an injury.
Bobrovsky started most of the games, and was named the Flyers playoff starter.
After Game 2 of the conference quarter-finals against the Buffalo Sabres, in which Boucher relieved Bobrovsky and earned the win, Boucher started the next three games.
However, he was pulled in Game 5 in favour of Leighton, who was called up as a third goaltender.
Leighton played well but lost Game 5 in overtime, nonetheless earning the start for Game 6.
However, in Game 6, Leighton allowed three goals in the opening period, and once again Boucher was able to earn the win in relief, making Boucher the only goaltender in NHL history to record two wins in a playoff series when coming in relief.
Boucher went on to start Game 7 as the Flyers defeated Buffalo.
Boucher started the first three games in the next round against Boston, but played poorly, allowing for deposed starter Bobrovsky to return in Game 4 as the Flyers were ultimately swept.
On July 1, 2009, Boucher agreed to a two-year contract with the Philadelphia Flyers to be the steady, veteran backup to the starting goaltender Ray Emery. However, when Emery incurred an injury midway through the season, Boucher was thrust into the spotlight with mediocre results. A hand injury soon pushed Boucher to the sideline, and he was replaced by third-string goaltender Michael Leighton. Leighton excelled in Boucher's absence, and once healthy, Boucher found himself backing-up Leighton. Upon the return of Emery, Boucher was further demoted to the press box, with Leighton now the backup. Emery soon re-injured himself, giving Boucher a chance to back-up Leighton, who once again was playing well. Near the end of the season, with only 13 games left, Leighton went down with a high-ankle sprain, and Boucher was back into the spotlight for the Flyers once again. After a 2–1 shootout victory in the final game of the season against the New York Rangers, Boucher and the Flyers advanced to the playoffs.
In the 2010 playoffs, Boucher defeated Martin Brodeur and the New Jersey Devils in the first round four games to one. The national media remarked he was the surprise of the playoffs after the first round with his outstanding play in net. The Flyers defeated the Boston Bruins in the second round by overcoming a three-game deficit, but Boucher was injured in Game 5 of that series with knee injuries. Boucher returned from his injuries to serve as a backup to Leighton in Game 1 of the Stanley Cup Finals against the Chicago Blackhawks. He saw game action in Game 1 and Game 5 in relief of Leighton, but the Flyers lost in six games to the Blackhawks.
In the 2010–11 season, Boucher split time in goal with standout rookie Sergei Bobrovsky after Leighton was demoted to the AHL, in part for hiding an injury. Bobrovsky started most of the games, and was named the Flyers playoff starter. After Game 2 of the conference quarter-finals against the Buffalo Sabres, in which Boucher relieved Bobrovsky and earned the win, Boucher started the next three games. However, he was pulled in Game 5 in favour of Leighton, who was called up as a third goaltender. Leighton played well but lost Game 5 in overtime, nonetheless earning the start for Game 6. However, in Game 6, Leighton allowed three goals in the opening period, and once again Boucher was able to earn the win in relief, making Boucher the only goaltender in NHL history to record two wins in a playoff series when coming in relief. Boucher went on to start Game 7 as the Flyers defeated Buffalo. Boucher started the first three games in the next round against Boston, but played poorly, allowing for deposed starter Bobrovsky to return in Game 4 as the Flyers were ultimately swept.
Brian Boucher