Hammon's second interview took place Monday, while Billups and D'Antoni are set for additional meetings with Portland officials in the coming days, sources said.
Billups has been in contact with several teams in this search process and remains with the Clippers in their Western Conference finals series against the Phoenix Suns. This is Billups' first season as an assistant coach in the NBA. He was a five-time NBA All-Star and was the NBA Finals MVP in 2004.
Hammon, who would become the first female head coach in NBA history, has been on Gregg Popovich's staff for seven seasons and has interviewed for several jobs in recent years. She was a six-time WNBA All-Star in her professional playing career.
D'Antoni is in his first season as Steve Nash's assistant in Brooklyn after spending the previous four seasons as the Houston Rockets' head coach. The two-time NBA Coach of the Year has a career 672-527 record in 16 seasons with the Rockets, Lakers, Knicks, Suns and Nuggets.
After a fourth first-round playoff exit in five seasons, the Blazers and coach Terry Stotts parted ways after nine seasons together. Stotts left Portland as the second-winningest coach in franchise history, including eight consecutive playoff appearances -- the longest streak in the league.
Portland's season ended with a 4-2 series loss to the Nuggets. Stotts led the Blazers to a 2019 berth in the Western Conference finals, plus two other trips to the conference semifinals, in his nine seasons with Portland.
Hammon takes over after Popovich gets ejected
Gregg Popovich argues a call and is ejected from the game vs. the Lakers and Becky Hammon steps in as head coach for the Spurs.