The Knicks have 16 players under contract for next season — one over the max — but there’s still a chance they are not done in free agency.

After inking Mario Hezonja on the first full day of free agency Sunday, the Knicks still could use a rebounding power forward and have inquired about Suns big man Alan Williams, according to an NBA source. Williams was waived Monday and must clear. The Knicks chased Williams hard last July before he opted to stick with Phoenix.

The 6-foot-7 Williams, 25, averaged 6.4 points and 5.7 rebounds over three seasons with the Suns after going undrafted out of Santa Barbara. He missed most of the 2017-18 season with a knee injury and was set to make $5.5 million next season. It was reported the Suns could re-sign Williams to a lesser deal if he clears waivers.

The Knicks are trying to make more roster moves by attempting to trade Courtney Lee’s and Joakim Noah’s long-term contracts.

If they sign Williams, the Knicks also may have to release rehabbing combo guard Ron Baker, who will miss summer league because of the February shoulder injury that ended his 2017-18 season.

The Knicks have a $3.4 million biannual exception or a minimum contract they could use on Williams. The Knicks have also inquired about power forwards Amir Johnson and Trevor Booker.

If the Knicks can’t trade Noah, he becomes a strong stretch-provision waiver candidate sometime after Sept. 1 to save 2019 cap space. The Knicks could invite Noah to training camp before making the call if they don’t sign anyone else and still need rebounding.

Team president Steve Mills and general manager Scott Perry said they wouldn’t “be players” in the free-agent market and might be done after one signing on the first day, likely pushing Michael Beasley onto the next chapter.

It is a roster nobody expects to make the playoffs — with a potential opening-night starting lineup of Enes Kanter at center, Hezonja at power forward, rookie Kevin Knox at small forward, Tim Hardaway Jr. at shooting guard and either Frank Ntilikina or Trey Burke as point guard.

The Knicks look more likely to battle for the No. 1 pick (Zion Williamson and R.J. Barrett are candidates) than the eighth seed.

On Tuesday in Las Vegas, the Knicks will gather for their first summer league practice with five players who will be on their main roster — Ntilikina, Damyean Dotson, Knox, second-round pick center Mitchell Robinson and second-year center Luke Kornet, who signed a one-year, $1.6 million deal Sunday.

The Knicks are allotted a pair of two-way G-League contracts, for which Allonzo Trier, the undrafted Arizona shooting guard, and power forward Isaiah Hicks are the favorites. Hicks was on a two-way deal last season. Both are on the summer league team that opens play Saturday vs. Atlanta and rookie point guard Trae Young.