Sacramento's interest stems in part from having a roster that has struggled mightily when it comes to defending shooters on various points on the floor.
Last season, the Kings were ranked 25th in the NBA in field goal percentage defense (.470) and 29th in three-point percentage defense (.377).
And with more and more versatile offensive players entering the league, the need for a do-it-all defender like Smart has apparently become more of a priority for the Kings franchise.
The Kings offered LaVine a four-year, $78 million contract which the Bulls matched almost immediately. Sacramento is unlikely to offer Smart such a lucrative deal, but it's expected to be closer to the $12-14 million salary that Smart was reportedly seeking in a new deal.
And at that price tag, it is far from a given that the Celtics will match the offer.
If Smart signs an offer sheet with the Kings and Boston declines to match it, it will be a blow to a Celtics defense that was among the best in the NBA last season.
Smart was drafted with the sixth overall pick by Boston in the 2014 NBA draft.
In his four seasons in Boston, Smart has averaged 9.4 points, 3.9 assists, 3.7 rebounds and 1.5 steals per game while shooting 36.0 percent from the field and 29.3 percent from 3-point range.
Shooting has been a clear weakness for Smart, but his defense and ability to make game-changing plays has made him a favorite of fans and the coaching staff who all greeted him enthusiastically when he showed up at the end of Boston's 100-80 summer league win over Charlotte.
Smart said he was meeting with his agent Happy Walters.