Karl-Anthony Towns left Monday's game against the Washington Wizards with a non-contact calf injury.
On Tuesday, ESPN's Adrian Wojnarowski reported that Towns is expected to miss 4-6 weeks with a calf strain. The Athletic's Shams Charania reported that the Minnesota Timberwolves forward avoided structural damage to his Achilles.
On social media, Towns vowed to "be back soon."
Towns collapsed on Monday while running up the court during the third quarter.
He clutched the back of his right calf and eventually needed help off the floor. He wasn't able to put any weight on his injured leg.
The Timberwolves later announced that he would not return to the game because of a calf strain. Head coach Chris Finch told reporters after the 142-127 Wizards win that he didn't have any further information on the injury.
"We'll have it evaluated tomorrow," he said.
Towns, 27, is coming off his second career All-NBA season. The Timberwolves made their first playoff appearance since 2018 behind Towns' strong play and the emergence of Anthony Edwards in his second NBA season. They traded for four-time All-NBA center Rudy Gobert in the offseason in an effort to build off the success of last season's playoff run.
A three-time All-Star, Towns is averaging 21.4 points, 8.5 rebounds and 5.4 assists this season. The Timberwolves entered Tuesday 10-11 and have struggled at times to adjust to the front line rebuilt around Towns and Gobert. While the news that Towns avoided Achilles damage is a relief in Minnesota, a month-long absence or more is a setback for the Timberwolves.