Indianapolis Colts quarterback Peyton Manning was cleared for workouts of greater intensity, though there still has not been a timetable established for a return to the field.

"X-ray and CT examination of the surgical area shows that the fusion performed in September has achieved firm fixation," said Dr. Robert Watkins in a statement issued following a conference call with Manning and Colts medical staff on Thursday.

"Peyton will now be allowed to increase the intensity and breadth of his workouts as tolerated. There remains every indication that his recovery will continue. There still is no timetable for Peyton���s return to practice, which is one of many steps in his expected return to game action. He is working hard on a rehabilitation program outlined in conjunction with myself, Erin Barill and Peyton. His response to this plan in the future will dictate his return date."

After starting every game for the Colts since 1998, Manning has missed the entire season with a lingering neck injury. The team has kept him on its active roster, hoping that he can at least practice.

"I am encouraged with what Doc had to say," Manning admitted. "I am happy that I can increase my rehabilitation program as outlined by him, Erin and the Colts Medical Staff. I am hopeful for continued progress in this next phase of my rehab."

Manning has endured three surgeries on his neck, including two in the past five months. He had a single level anterior fusion surgery on September 8 and was cleared to leave the booth and stand on the sidelines in early October.

Without its franchise cornerstone, Indianapolis has struggled mightily, going 0-11 heading into a Sunday night meeting against the New England Patriots. The Colts have not had a winless season since an 0-8-1 finish to the strike- shortened 1982 campaign, but have not finished a full regular season without a victory in their history.

Veteran Kerry Collins started three games, but was lost for the year with a concussion. Third-year quarterback Curtis Painter has started the last eight games, while Dan Orlovsky has seen action in three contests.