Serving as the GM in Arizona is an upward career move for Hazen. With the Red Sox, Dombrowski runs the front office.
Hazen will get that opportunity with the D-backs, reporting directly to team president and chief executive officer Derrick Hall.
"I'm extremely grateful for this incredible opportunity to help the D-backs reach the next level," Hazen said. "This is a franchise that has experienced a lot of success -- both on and off the field -- in less than two decades of existence, and I'm looking forward to working with [owner] Ken [Kendrick] and [president] Derrick [Hall] to help bring back a tradition of winning to Arizona."
"We are extremely happy for Mike and his family as they begin this new opportunity in Arizona," Dombrowski said in a statement. "As one of the most respected young baseball executives in the game, Mike is more than deserving of this position. On behalf of the club, we would like to thank Mike for his 11 years of service to the Red Sox and wish him well in his new role. He will be missed by all of his colleagues here at the Boston Red Sox. In the meantime, a search for a new general manager for the Boston Red Sox is underway."
Out of respect to MLB's regulations regarding announcements during the postseason, Dombrowski will withhold further comment until a Monday morning conference call with the media.
In Allard Baird and Frank Wren, the club has two former GMs working in its front office under Dombrowski. Assistant general manager Brian O'Halloran could also emerge as an internal candidate to replace Hazen. Vice president of international and scouting Amiel Sawdaye is another in-house candidate who could receive consideration.
Hazen, a Massachusetts native, was hired by the Red Sox in 2006 as director of player development and slowly worked his way up the ladder, eventually being promoted to a VP and assistant to Cherington, who spent the 2015-16 academic year teaching at Columbia University and was hired last month as the Blue Jays' VP of baseball operations.
A Princeton grad and former Minor League outfielder, Hazen began his front-office career with the Indians, working in their scouting and player development department.
Ian Browne has covered the Red Sox for MLB.com since 2002. Follow him on Twitter @IanMBrowne and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.