Tiger Woods said he was not surprised with his impressive start to the Open Championship at Hoylake despite a season curtailed by injury.
The 14-time major champion began with two bogeys but fought back for a three-under-par 69 to be three off the lead.
Woods, 38, had back surgery in March and has only played once since.
He said: "I knew I could do it. I felt good about a lot of things I did out there, especially to fight myself back into the championship."
The world number seven, whose last Open win came at Hoylake in 2006, returned from his lay-off at Congressional last month and, although he missed the cut, he was reassured by the way his back responded.
Back at Hoylake, eight years after that emotional win in the wake of his father's death, Woods got off to an ignominious start.
He found a difficult sloping lie in a greenside bunker on the first and fired the ball across the green en route to a bogey five. And he made a "sloppy" three-putt bogey five on the second but said he was able to keep his discipline.
"I still had four par fives to play," he said. "I'm not going to be the only guy to make two bogeys over 72 holes. I just got mine out of the way early."
He pulled a shot back at the long fifth and holed a good putt on the 11th to begin a run of five birdies in six holes.
Asked if it reminded him of the old days, Woods replied: "It wasn't that long ago. I did win five times last year."
The American, however, suggested there was plenty of room for improvement as he chases a first major title since 2008.
"I need to get everything a little better," he said. "At Congressional I made just some terrible mistakes mentally. My decisions weren't very crisp and I wasn't decisive enough.
"Today was totally different and consequently I shot a better score."
|Tiger Woods's major titles|
|Masters:||US Open:||Open Championship:||US PGA:|
|1997, 2001, 2002, 2005||2000, 2002, 2008||2000, 2005, 2006||1999, 2000, 2006, 2007|
Woods backed off a number of shots, notably his second to the 18th, and bemoaned photographers and fans using mobile phones.
"Unfortunately, people just don't put their phones on silent," he said. "And some of the professional guys were getting on the trigger early.
"There's a lot of moving parts out there. You've just got to stay focused."
Open organisers the R&A have been keen to promote the use of mobile devices to follow the action on the course, but it issued a statement reminding spectators to keep their phones on silent and not to take photos on championship days.
The Masters polices a strict no-phone policy, while cameras are similarly not allowed on tournament days.