 Geist began his career as an editor and producer for CNN Sports Illustrated and subsequently a field producer and reporter for CNN Sports, where he covered the Super Bowl, the NCAA Final Four, and The Masters.Geist began substituting as a co-host on MSNBC's 6–9 a.m. morning time slot almost immediately after Don Imus was fired in late April 2007.Geist was named permanent co-host of "Morning Joe", along with Joe Scarborough and Mika Brzezinski in September 2007.