Rundblad's first NHL point was an assist on a goal by Peter Regin on 15 October in a game against the Washington Capitals.

[6] On 17 December 2011, Rundblad was traded to the Phoenix Coyotes (along with a second-round draft pick) for forward Kyle Turris.

On 4 March 2014, Rundblad (along with defenceman Mathieu Brisebois) was traded to the Chicago Blackhawks in exchange for a second-round pick in 2014.

In the 2015–16 season, Rundblad made the Blackhawks opening night roster primarily as the team's reserve defenseman.

Before playing with Rockford, on 3 January 2016, it was announced that Rundblad was loaned to the ZSC Lions of Switzerland's National League A for the remainder of the season.

[12] On 23 June 2022, Rundblad left the KHL following three seasons with Sochi and moved to the Finnish Liiga on a one-year contract with Kärpät.