The Spurs want to add Kristaps Porzingis this summer.

San Antonio has “significant interest” in attempting to sign the star 23-year-old Knicks forward when he becomes a restricted free agent after the season, according to a report from The Ringer, which cites unidentified front offices sources.

But, it is unclear how San Antonio would create the cap space required to ink Porzingis to a max offer sheet, the report says.

Porzingis has not played this season as he continues to recover from a torn ACL he suffered in February 2018. There is no timetable for his return.

New York originally selected Porzingis with the fourth pick in the 2015 draft. He averaged a career-best 22.7 points and shot 39.5 percent from 3-point range in 2017-18.

The Knicks will enter their matchup against the Warriors on Tuesday with a 10-30 record. They last made the playoffs in 2012-13.