According to the report, the deal would be for five years and worth more than $120 million.
Lillard, 24, averaged a career-high 21 points per game last season, to go along with 6.2 assists and 4.6 rebounds while playing in all 82 regular-season games.
His scoring average has increased in his each of his three NBA seasons, after the team selected him in the first round of the 2012 NBA draft. He went on to win the NBA’s Rookie of the Year award and has made the All-Star team in each of the last two seasons.
Lillard is set to make $4.2 million next season, part of his original four-year rookie deal.
Players drafted in the first round of the 2012 NBA draft can negotiate contract extensions through Oct. 31, but can't officially sign any deal until July 9, when the league's moratorium on player business is lifted.
Portland has already reportedly signed former Dallas Mavericks forward Al-Farouq Aminu to four-year, $30 million deal as reports surface that All-Star forward LaMarcus Aldridge is not expected to re-sign with the team.
- Scooby Axson