Pedersen began his career with Tromsø, then played for English side Blackburn Rovers between 2004 and 2013 making a total of 349 appearances.

[4] The Norwegian international made his Premier League debut in a 1–1 draw against local rivals Manchester United on 28 August 2004, a match Blackburn were leading until deep into injury time.

He initially struggled to make an impact in the Premier League and had lengthy period of not being selected after Souness was replaced by Mark Hughes as the Blackburn manager in September 2004.

[8] After a year of transfer negotiations, Blackburn announced that Pedersen had signed a new four-year deal at Ewood Park on 19 May 2010, which would see him stay contracted until the summer of 2014.

Blackburn chairman, John Williams, who completed the formalities of the deal, added: "Sam made this, together with finding a striker, being our summer priority.

Four days later, he netted against Newcastle United at St James' Park, scoring in the third minute with his right foot following an assist from Brett Emerton and he also took a punch to the stomach by Joey Barton.

On 24 August 2011, Pedersen captained Blackburn in their 3–1 win over Sheffield Wednesday at Ewood Park in the second round of the League Cup.

[12] On 30 August 2013, he joined the Turkish side Karabükspor on a free transfer, after he had made 288 league appearances for the Ewood Park outfit.

At the end of his Rosenborg contract he remained in the top division of Norwegian football returning to his first senior club, Tromsø.

[15][16] After the match against Hungary, he received the coveted Golden Watch award given to him by the Football Association of Norway on the occasion of his 25th appearance for his country.

[14] Gamst Pedersen was left off of the squad for the 2014 World Cup qualifying matches against Iceland and Slovenia in September 2012,[18] and was not called up for the national team for over a year when on 11 November 2013 he was included in Per-Mathias Høgmo squad for the friendly matches against Denmark and Scotland after Daniel Braaten called absent due to an injury.

[20] Pedersen fronted Norwegian boyband The Players, alongside fellow footballers Freddy dos Santos, Raymond Kvisvik, Kristofer Hæstad and Øyvind Svenning.