The club Manchester United, where Lindelöf plays, confirms to Aftonbladet that it was the football star who stopped the bag thief.
The 90-year-old had his bag in the basket in the walker and the bag thief stole it on the go when he cycled past.
Victor Nilsson Lindelöf witnessed the incident, ran after it and then held the man until the police arrived.
On their website, the police write that they thank "the witness for a quick and wise intervention".
The man who stole the bag was arrested at the scene on suspicion of aggravated theft and minor drug offenses.