Greg Oden admits it: He considered retiring before he turned 25. He, too, wondered if his ongoing knee problems would allow him to play basketball again. But there was Oden on Thursday night, back on the floor, playing for the Miami Heat in a victory over the Los Angeles Lakers, his fourth game this season after a four-year layoff. "It was a long four years," Oden said. "But now I'm back, I'm healthy and I'm just happy to be doing it." Thursday night was a long way from that June 2007 night when the Portland Trail Blazers took Oden as the No. 1 pick, ahead of Kevin Durant. Durant has become an MVP candidate and a five-time All-Star now while Oden had played just 82 games – the length of a single season – in the 6½ years after that draft before he officially made his debut for the Heat on Jan. 15. Oden's knee problems began before he even played his first minutes in the NBA. He missed his initial rookie season after undergoing microfracture surgery on his right knee. He missed 15 games during the following season with a bone chip in his left knee. He missed the final 61 games of the 2009-10 season to repair a fracture in his left patella. Two microfracture surgeries on his left knee followed, sidelining him indefinitely. Before joining the Heat, he last suited up on Dec. 5, 2009. "It was very tough," Oden said. "Last year at this time I was sitting at home."