"I definitely wanted to get it done before the season started," he said. "I know it was something the Ducks had mentioned, that they wanted to do as well. … So it is a little bit of a relief to have it done."
Manson, 25, has 35 points (10 goals, 25 assists) and is plus-26 in 181 games with the Ducks. He had 17 points (five goals, 12 assists) and was plus-14 as the only Anaheim defenseman to play 82 games last season.
"I hope I continue to progress as the years go along," Manson said. "I still feel I haven't reached my potential. There's areas of my game where I'd like to keep improving. As time goes along, I hope to be a better player at the end of this contract than I was at this point when I'm signing it."
He was selected by Anaheim in the sixth round (No. 160) of the 2011 NHL Draft, and since his NHL debut on Oct. 31, 2014, leads Ducks defensemen in hits (426) and hits per game (2.4).
He is playing the final season of a two-year contract worth $825,000 annually, according to CapFriendly.com.
"I just want to play my style of game," Manson said. "Hopefully, I can contribute on the offense a little bit more than I have in years past. Play that physical style of game and defend against every player that other teams can throw our way."
NHL.com staff writer Lisa Dillman contributed to this report.
