Isaiah Hartenstein meeting with Thunder as Knicks face uphill climb to keep him

The Knicks’ competition gave its pitch.

Oklahoma City, a contending team flush with salary-cap space, sat with Isaiah Hartenstein on Sunday in the opening hours of free agency, a source confirmed.

The Thunder traveled to Hartenstein in Eugene, Ore., where the Knicks center was born and still has family.

According to NBA newsbreaker Shams Charania, the purpose of the Thunder’s visit was to “pitch [Hartenstein] aggressively on coming to Oklahoma City.”

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There was no word of a decision late Sunday night, with much of the NBA awaiting a commitment from the 2024 class’s top free agent, Paul George .

The Knicks want to keep Hartenstein, but need to subtract salary from their books just to make him a max offer of four years, $72.5 million.

As The Post reported weeks ago , the Thunder, which can overwhelm the Knicks’ offer using cap space, was viewed as the top threat to pry Hartenstein away in free agency.

After earning the Western Conference’s top record last season, the Thunder and its pragmatic team president, Sam Presti, can offer an opportunity for a championship.

League sources speculated, however, that the Thunder would rather offer Hartenstein a short-term deal like two years with a player option to maintain future flexibility.

Last season, the Thunder started the lanky Chet Holmgren at center.

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His 3-point shooting spaced the floor but OKC was one of the NBA’s worst rebounding teams, hence the desire for a physical paint presence like Hartenstein.

It’s unclear if the Thunder, which entered free agency with over $30 million in cap space, was planning to start Hartenstein or bring him off the bench.

Heading into free agency, the Pistons, 76ers, Magic and Spurs all had enough cap space to outbid the Knicks.

Hartenstein is coming off a year in which he averaged career-highs in rebounds (8.3), minutes (25.3) and steals (1.2), emerging as the Knicks’ starting center after Mitchell Robinson underwent ankle surgery.

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He thrived under Tom Thibodeau, but the Knicks only have his Early Bird Rights — not his full Bird Rights — and can’t offer much more than a starting salary of $16 million.

It’s noteworthy that the meeting in Oregon occurred on the opening day of free agency, symbolizing that OKC, which has had trouble recruiting free agents to its small-market franchise, made Hartenstein its priority.

In a weak market, the 26-year-old Hartenstein probably represents the top center available in free agency. A comparable Nic Claxton just re-signed with the Nets for four years, $100 million.

Hartenstein made his mark with the Knicks after bouncing around the league, going from the Rockets to the Nuggets to the Cavaliers.

Thibodeau’s Knicks would obviously love to keep him.

But now they can only wait.

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