The NFC West rivals meet for the first time this season at the weekend, having each won one of their two meetings in 2012.
The Seahawks head coach told reporters: "I thought he looked great during the stretch in the postseason last year and was really on it. He was able to make all the throws that he needed, a lot of downfield throws.
"[The 49ers's win over the Green Bay Packers on Sunday] was really an extension of that. You can see the belief in him from the coaching staff. They trust him and they went for it."
The Seahawks beat the 49ers 42-13 when the teams met in week 16 last season.