We continue our countdown of the greatest 30 players to turn out in the green-and-white of Celtic.
After Danny McGrain at number 22, the number 21 spot on our countdown of the greatest 30 Celtic players of all time goes to another hardened defender who was a driving force in a successful period for the club.
Although he had begun his career as a tough-tackling midfield player at AIK in his native Sweden, Johan Mjallby made his name at Parkhead as a mainstay in the Bhoys defence under Martin O'Neill.
His time in Scotland started in the best possible fashion after he was signed by Jo Venglos for £1.5 million in 1998, making his debut in the 5-1 thrashing of Rangers.
Mjallby would become an integral rock in O'Neill's three-at-the-back system favoured during the Northern Irish manager's early days in charge of the Hoops, and quickly became the side's primary defensive enforcer in the back line.
Dominant in the air at both ends of the pitch, the Swedish international became virtually irreplaceable in the Celtic team that won three league titles in the space of four years at the start of the 2000s.
He was also one of the most consistent performers in the team's run to the UEFA Cup final in 2003, where they ultimately had their hearts broken by Jose Mourinho's Porto.
Mjallby's final season at Celtic Park was hampered by injury, and he left for Spanish side Levante in 2004 at the age of 33 after making nearly 200 appearances for the Bhoys.
After hanging up his boots he would return to the club as Neil Lennon's assistant manager in 2010, staying for four years before following his former teammate to Bolton Wanderers.