The Raiders also hired former Patriots offensive line coach Carmen Bricillo for the same job in Las Vegas, a source said.
Lombardi, 33, replaces Greg Olson, who had served as Raiders offensive coordinator since being brought in with Jon Gruden in 2018. Lombardi handled the Patriots' red zone game plan last season and McDaniels noted that he sees the offense similarly to him.
Lombardi is the son of Michael Lombardi, the longtime NFL front-office executive who served as a senior executive with the Raiders from 1998 to 2007.
Mick Lombardi broke into the NFL as a scouting assistant with the Patriots from 2011 to 2012, before moving on to the San Francisco 49ers from 2013 to 2016 as a coaching assistant on offense and defense. He spent the 2017-2018 seasons with the New York Jets before returning to the Patriots in 2019.
In addition to working with receivers in New England, he had been an assistant quarterbacks coach.
Lombardi and Bricillo are the latest members of the Patriots staff to follow new Raiders head coach Josh McDaniels to Las Vegas. Former Patriots quality control/QB coach Bo Hardegree recently agreed to become the Raiders' new quarterbacks coach.
This has left some major voids for Patriots coach Bill Belichick to fill, in addition to the expected retirement of running backs coach Ivan Fears. The only new offensive coach the Patriots have announced they've hired is Joe Judge, their former special teams/receivers coach who spent the past two seasons as New York Giants head coach.
Also of note on McDaniels' staff is Rob Ryan. Previously, the Raiders defensive coordinator from 2004 to 2008, Ryan is rejoining the team as a senior defensive assistant under new defensive coordinator Patrick Graham. Ryan was the Baltimore Ravens inside linebackers coach last season.
ESPN staff writers Mike Reiss and Paul Gutierrez and The Associated Press contributed to this report.