Center Isaiah Hartenstein, the Thunder's key offseason signing, will not be ready for the start of the 2024-25 NBA season next week after suffering a "small, non-displaced fracture in his left hand" Tuesday night at Denver, the team announced Thursday morning.

Hartenstein will be re-evaluated in five to six weeks.

Through three preseason appearances, the Thunder inserted Hartenstein into its lineup as both a starter and a reserve.

Hartenstein, a skilled bruiser who was meant to aid in OKC’s rebounding and playmaking efforts, will look on at a Thunder lineup that reverts to an awfully familiar image. Still, much of the core remains from a team that won 57 games a season ago.

“We got a great group of guys with Hartenstein and without,” fourth-year wing Aaron Wiggins said at Thursday’s shootaround. “Obviously the anticipation of playing with him and Alex Caruso and guys like that was high, but good things come to those who wait.

“We’ll get better and kind of find things with his absence, but when he returns we’ll be just as fluid and probably ready to go at that point.”

The Thunder signed Hartenstein to a reported three-year, $87-million deal at the start of NBA free agency in July.

Hartenstein, a second-round pick by the Rockets in 2017, has averaged 6.0 points and 5.7 rebounds per game in his NBA career. He is coming off his best season in the league in 2023-24, when he averaged 7.8 points and 8.3 rebounds with the Knicks.

OKC hosts Atlanta at 7 p.m. Thursday in its preseason finale before opening the regular season next Thursday at Denver.

More: What does Isaiah Hartenstein's injury mean for OKC Thunder frontcourt options?

Isaiah Hartenstein stats

• 2023-24 with New York Knicks: 75 games played, 49 games started, 8.5 points per game, 7.8 rebounds per game

• Six-year NBA career: 322 games played, 61 games started, 6.0 points per game, 5.6 rebounds per game

(This article has been updated to add new information.)

This article originally appeared on Oklahoman: Isaiah Hartenstein injury update: Thunder center suffers broken hand