Boston Celtics star Kemba Walker was taken to hospital with "concussion-like symptoms" after a scary collision against the Denver Nuggets on Friday.

With his head down, Walker bumped into team-mate Semi Ojeleye during the second quarter at the Pepsi Center.

Amid fears the three-time All-Star had suffered a neck injury, the Celtics announced Walker was taken to hospital.

"Kemba Walker has been diagnosed with concussion-like symptoms. He is being transported to the hospital for further evaluation," the NBA team wrote on Twitter.

"Further updates will be provided as appropriate."

Walker had contributed three assists and a rebound in 12 minutes before his injury.

The 29-year-old had been averaging 22.6 points, 4.9 rebounds and 4.8 assists per game heading into the clash against the Nuggets.