Tiger Woods announced Monday that he has completed a “private intensive program” and will “continue to tackle” an unspecified issue.

Woods did not make an appearance last week at the tournament he hosts, the Quicken Loans National, which was held in Maryland at TPC Potomac at Avenel Farm. He used his Twitter account Sunday to congratulate the winner, Kyle Stanley, and to thank those who played in, attended and staffed the event.

“I recently completed an out of state private intensive program,” Woods tweeted Monday. “I will continue to tackle this going forward with my doctors, family and friends. I am so very thankful for all of the support I’ve received.”

Woods underwent back surgery in April, his fourth such procedure in the past three years, as he has struggled to revive his flagging golf career. The 41-year-old, who has not won a major championship since the 2008 U.S. Open, has barely played in recent years, although he has frequently expressed confidence in his form and his physical state.

In May, Woods was arrested for driving under the influence near his home in Jupiter, Florida. A breathalyzer revealed no alcohol in his system, and he blamed the incident on prescription drugs, saying in a statement, “I didn’t realize the mix of medications had affected me so strongly.”

The 14-time major winner said last month that he was “receiving professional help to manage my medications,” citing “back pain and a sleep disorder.”

Dash-cam footage taken by police during the arrest showed Woods appearing unsteady, disoriented and struggling to comply with sobriety tests. “I understand the severity of what I did, and I take full responsibility for my actions,” he said in his statement.

Five days before his arrest, Woods wrote on his website, “It has been just over a month since I underwent fusion surgery on my back, and it is hard to express how much better I feel. It was instant nerve relief. I haven’t felt this good in years. … I had nerve pain with anything I did and was at the end of my rope.”

“I want to say unequivocally, I want to play professional golf again,” Woods added.

Woods was originally scheduled to appear in court Wednesday, but an arraignment for his DUI charge was pushed back to Aug. 9.