Tiger Woods says he needs to keep pouring in birdies to be able to launch a weekend challenge at the CIMB Classic.
The world number two has managed 13 in his two rounds so far but still trails halfway leader Robert Garrigus by five shots on the soft Mines Resort and Golf Club course where the winning score is predicted to be somewhere between 20 and 25 under.
Woods, who is nine-under and in tied fifth at halfway, said: "You have to make birdies out there. You can't just be passive and play to the centre of the greens and stuff. You have to be aggressive. Guys are taking it low."
Of his second round 67, he said: "It was just one of those days that I didn't make enough birdies. I didn't really have a lot of looks, and then the looks I did have were downhill, cross grain putts and putts that I just couldn't be aggressive with."
Garrigus, meanwhile, is having a blast after shooting his second successive 64 to reach 14-under and take a two-shot lead.
"I feel like I can beat anybody in the world. I've played with Tiger. I've played with Rory (McIlroy) in the Tour Championship. I hit it just as good as those guys. It's just the short game.
"If I'm putting well and if I keep putting like this on the weekend, it's going to be hard to catch me," said the 34-year-old.
"I do have a very high confidence level right now. I had one of the best years of my career. I'm having fun, having a good time with it. A lot of my hard work is paid off and that's nice to see."