The Portland Trail Blazers have announced via a press release that center Greg Oden will undergo microfracture surgery on his left knee, ending his 2010-2011 NBA season before it started.

Oden fractured the patella in his left knee in a game against the Houston Rockets last December. His rehabilitation had been a slow, start-and-stop process, marred by knee pain and continual delays.

Here's the full press release from the Portland Trail Blazers.

PORTLAND, Ore. - Portland Trail Blazers center Greg Oden will undergo microfracture surgery on his left knee Friday and will miss the remainder of the 2010-11 season, the Trail Blazers announced this evening.
 
Dr. Richard Steadman will perform the surgery with assistance from Trail Blazers orthopedic surgeon Dr. Don Roberts at the Steadman Hawkins Clinic in Vail, Colo.
 
Oden, 22, has been sidelined since fracturing his left patella in a Dec. 5, 2009, game vs. Houston. A recent MRI showed damaged cartilage to the surface of his femur, and his current injury is unrelated to the fractured left patella.
 
Oden previously underwent microfracture surgery on his right knee Sept. 13, 2007.
 
He holds career NBA averages of 9.4 points, 7.3 rebounds, 0.6 assists and 1.43 blocked shots in 82 games over parts of two seasons from 2008-09.

The Blazers will hold a press conference tonight. More coverage from that as soon as possible.

-- Ben Golliver | benjamin.golliver@gmail.com | Twitter