Nicknamed Ísafjarðartröllið (English: The Ísafjördur Troll),[1][2][3][4] he won the Icelandic championship four times during his career, in 2008, 2012, 2013 and 2023.

In September 2015, Sigurður signed with the Greek 2nd Division team Machites Doxas Pefkon,[8] where he averaged 11.9 points and 7.9 rebounds per game.

[13] On 1 April 2019, he scored 16 points in ÍR's victory in game 5 of its first-round playoff series against second seeded Njarðvík.

[16] Two days before the first game of the season, the French Basketball Federation declared that the Orchies did not fulfill their required financial obligations and as a result Sigurður was released from his contract.

[18] Only 9 minutes into his first game back, he suffered a season ending injury after tearing a cruciate ligament in his knee.

[20] In August 2020, Sigurður sued ÍR for missing salary payments and claimed the team owed him over 2 million ISK.

[21] On 17 November 2020, the District Court of Reykjavík ruled that ÍR owed Sigurður two million ISK in back pays plus penalties.

[25] On 30 April, he had 20 points and 9 rebounds in Tindastóll's game four series deciding victory against Njarðvík in the semi-finals of the Úrvalsdeild playoffs.