Detroit announced the moves Tuesday. The 23-year-old Pulkkinen has 30 goals and 27 assists in 44 games for Grand Rapids this season. He's also played six games with the Red Wings in 2014-15, scoring his first NHL goal Jan. 20 against Minnesota.
The 23-year-old Mrazek stepped in for Detroit when Jimmy Howard went down with a groin injury last month. Mrazek has appeared in 20 games for the Red Wings this season, going 13-5-1 with a 2.55 goals-against average.
Howard is back now, so Mrazek was sent to the minors.