"Kevin has been one of our most consistent performers over the last three years," said general manager Doug Armstrong. "In each of his first three seasons, Kevin has finished in the Top 25 in scoring by a defenseman and we expect him to continue to be among the NHL leaders."
The 24-year-old Shattenkirk had five goals and 18 assists in 48 games last season. In four NHL seasons with Colorado and St. Louis, the former Boston University player has 23 goals and 86 assists in 201 games.
The 25-year-old Berglund, from Sweden, had 17 goals and eight assists in 48 games last season. In five seasons with the Blues, he has 92 goals and 96 assists in 358 games.