He was a longtime 49ers assistant who won two SB's as a member of the coaching staff. He coached the DL from 1989 until 1994, when he switched over to LB's. After Pete Carroll left, he moved up to defensive coordinator in 1997. He then later worked as a defensive coordinator on George Seifert's staff in Carolina, working alongisde future 49ers OC Greg Roman. He was a long time defensive coordinator on Mike Holmgren's staff in Seattle after that.
Marshall spent more than 30 years as an assistant in the NFL with his greatest success coming in San Francisco, where he won two Super Bowl titles. Marshall was the defensive line coach on the 1989 title team and linebackers coach in 1994. He also served two years as defensive coordinator.
Marshall also coached for Green Bay, Atlanta, Indianapolis, Carolina, Detroit, Seattle and the Raiders. He was a coordinator for more than a decade, including his final two seasons in the NFL with the Raiders in 2009 and 2010.
https://abc7news.com/sports/longtime-assistant-john-marshall-who-won-two-super-bowls-with-san-/11202837/
