Oklahoma City Thunder center Isaiah Hartenstein will miss additional time after straining his left calf for the second time this season. Hartenstein was ruled out of Monday night’s game against the Atlanta Hawks after exiting Sunday’s win over the Philadelphia 76ers late in the third quarter.
Isaiah Hartenstein Aggravated Left Calf Injury
The Thunder did not announce a timetable for Hartenstein’s return. He missed six games after straining his left soleus on Nov. 26, returning 17 days later.
Through 24 games (all starts) this season, Hartenstein is averaging a career-high-tying 11.2 points, 10.4 rebounds, 3.0 assists, 1.1 steals, and 26.9 minutes per outing while shooting 64.4% from the field and 64.9% from the foul line.
Per Basketball Reference, the 7-footer leads the NBA in defensive rating (102.6) and ranks 17th in total rebounds (249), 16th in offensive rebounds (81), and fifth in defensive box plus/minus (2.3).
In Oklahoma City’s 132-101 win at Sacramento on Nov. 7, he recorded a career-high 33 points on 14-of-17 (82.4%) shooting from the floor and 5-for-6 (83.3%) from the free throw line.
Thunder center Isaiah Hartenstein is out vs. Hawks tonight due to a left soleus strain. It’s the second strain of that calf for him this season. He missed six games after originally injuring it on Nov. 26.
— Tim MacMahon (@BannedMacMahon) December 29, 2025
Hartenstein, 27, signed a three-year, $87 million contract with the Thunder in July 2024. In addition to him earning $28.5 million this campaign, his deal includes a 2026-27 player option worth the same amount.
Oklahoma City’s frontcourt depth has also been depleted by the absence of backup center Jaylin Williams, who was ruled out for a seventh consecutive game Monday with right heel bursitis.
If Hartenstein misses an extended period of time again, the expectation is that Cason Wallace will take over as a starter and Chet Holmgren will move over to center.
Thunder Defeated Hawks
The NBA-leading Thunder (28-5) handed the Hawks their seventh straight loss on Monday night. Reigning MVP Shai Gilgeous-Alexander led Oklahoma City with 39 points.
Gilgeous-Alexander scored at least 20 points for the 104th consecutive game. The three-time All-Star guard also put up 15 of Oklahoma City’s 35 first-quarter points.
Holmgren finished his performance with 24 points, nine rebounds, and three blocks, while Jalen Williams added 20 points, nine rebounds, and seven assists.
The Thunder host the Portland Trail Blazers on Wednesday.
