By Steve Keating

AUGUSTA, Georgia (Reuters) - It was a rousing return to happier times for Tiger Woods on Thursday as the disgraced world number one rode the support of cheering fans to surge into contention in the U.S. Masters first round.

No-one, particularly an anxious Woods, could have been sure of the crowd's reception on his return from self-imposed exile after revelations about his tawdry extra-marital affairs.

However, Woods could not have dreamed of a warmer welcome or better score from his first competitive golf in 144 days.

Playing under crushing scrutiny, it was a remarkable display by the American who finished with a pair of personal Masters firsts, including a four-under 68, marking the first time in 16 trips to Augusta that he had broken 70 in the opening round.

His round also included two eagles -- another personal best at Augusta -- helping him to finish two strokes behind leader Fred Couples.

More than his sparkling play, however, it was the glowing reception that proved most satisfying for Woods.

"It was unbelievable all day, the people I haven't heard them cheer this loud in all my years here," said Woods. "It helped me keep my spirits up.

"Off to the first tee, and pretty much all day, it was just incredible."

There was little doubt that the vast majority of golf fans were excited to see the four-time champion back at Augusta.

From the first hole to the last, Woods was greeted by robust applause and encouragement, the massive gallery trailing him shouting loud and often: "We love you Tiger."

Asked if he heard any negative comments, Woods answered, "absolutely not."

"I was pretty calm all day, I felt I was just trying to plod along and not throw any shots away," said Woods. "I'm very pleased.

"Why enter an event you don't think you're going to win?

"That doesn't change. (If) I don't feel like I can win then I won't enter the event."

Despite the warm welcome back, the scandal that has engulfed the 14-time major winner for nearly five months has yet to fade.

The plane continued to torment Woods throughout his round, reappearing again as he made the turn towing a new sign: "Sex addict? Yeah right. Sure me too."

There are sure to be more humiliating reminders this weekend given one of Woods's alleged mistresses, porn star Joslyn James, is scheduled to perform at an Atlanta strip club alongside a line-up of look-alikes of his Swedish wife Elin Nordegren.

Despite the distractions, for one day at least, the focus was primarily on the American's golf, rather than his indiscretions.

The 34-year-old stepped onto the first tee cleanly shaven having removed the goatee he had sported since arriving at Augusta National.

Woods had pledged during an interview on Monday to give the fans and the game more respect and try to tone down his anger and occasional profanity-laced outbursts.

Tested at times by wayward shots that were scrutinized by enormous galleries, Woods mostly held his composure while acknowledging the crowd support, routinely tipping his cap and saying 'thank you'.

There were fewer fist pumps and bursts of excitement after a sensational shot -- and there were more than a few -- but Woods could not hide his delight at being back.

He was back to more familiar form in his post-round interview, however, where he was evasive about everything but his shot-making.

Asked what the day meant to him, his reply was prickly and vintage Woods.

"It means I'm two shots off the lead," he said.

While question marks remain over Woods's private rehabilitation, the world number one left few in doubt about his ability to deliver on the course.

A sublime rescue shot that resulted in a birdie at the ninth, prompted one fan to turn to his friend and remark: "He's still the greatest golfer on the planet."

(Editing by Ian Ransom; To query or comment on this story email sportsfeedback@thomsonreuters.com)