Lawrence Frank has the NBA's richest contract for an assistant head coach.

Frank has signed a four-year, $4 million deal with the Brooklyn Nets.

Mike Malone was previously the NBA's richest assistant as $750,000 per season with the Golden State Warriors. Malone left the Warriors to become head coach of the Sacramento Kings this offseason.

Frank was most recently head coach of the Detroit Pistons.

A league source said Frank's deal with Brooklyn "could be the biggest in league history for an assistant."