Olsson was named Albion's vice captain by Roberto Di Matteo in August 2009.
He proved a towering influence in helping the Baggies clinch automatic promotion back to the Barclays Premier League at the first attempt with his full-blooded displays at the heart of defence.
The passionate centre-half was a virtual ever-present last term and his form saw him earn his first-ever senior Sweden cap in a 1-0 friendly win over Belarus in June 2010.
He joined the Baggies on the penultimate day of the 2008 August transfer window in an £800,000 move from NEC Nijmegen. The 6ft4in left-sided defender penned a two-year contract, plus a further year's option in the club's favour.
The fee for the former Sweden Under-20 and Under-21 international was set to rise by a further £360,000 in performance-related add-ons.
Olsson made his Baggies debut in a 3-2 win over West Ham at The Hawthorns in September 2008 and quickly became one of the first names on the team-sheet.
He scored five times last term to add to his three the previous season, which included the only goal of the game at Middlesbrough in September and the opener in April's 3-0 home win over Sunderland.
Unfortunately, Olsson was forced to sit on the sidelines for more than two months, between January and March of Albion's 2008/09 Barclays Premier League season, with tendonitis and bone bruising to his knee.
During that time his never-say-die attitude at the heart of the Baggies defence was sorely missed.
After moving to Holland from home-town club Landskrona in 2005, Olsson was an Eredivisie regular for Nijmegen for three years, helping them finish tenth in his first two seasons and eighth in 2007/08.
Olsson also clocked up 20 Under-21 caps for his country. (LAST UPDATED SEPTEMBER 2, 2010)