That focus meant she didn't even realize she'd shot a round-best 6-under par 65 on Friday at the Manulife Financial LPGA Classic at Grey Silo Golf Course to tie Hee Young Park for the tournament lead.
"I have a habit that I don't really look at the scoreboard during the play, so until you tell me, I don't really know that I'm leading," said Feng. "Today the wind was not as strong so I'm pretty sure the girls had better scores today.
"I heard the weekend's supposed to be nice, so we have to go for many, many birdies."
Park fired a second round score of 5-under par 66, a two-day total of 11 under, to maintain her joint lead at the event. Park was tied with Michelle Wie after the first round at 6-under 65 and she continued to shoot well, putting together her second bogey-free round. Feng also had a clean round, with six birdies for a 65 on the day.
Park said she used the same approach as the first round, despite the lack of wind on Day 2.
"I still hit a lot of greens and my goal was try to leave uphill putts. That worked well today," said Park, the defending Manulife Financial LPGA Classic champion. "I think that makes me more comfortable today."
Park said even though she has the lead after two rounds, she was reluctant to get too confident.
"I think it's still too far away to say something," she said. "I'm not going to think about later or not, just keep on doing my same playing."
Even though her scorecard was flawless, Feng said she did leave some shots on the course. With three finishes in the top 10 this season, Feng is hungry for her first win and believes she is in a good position to get it.
"My goal this year is to win three tournaments on the LPGA and now I'm zero. If I win here, I get one, that's one down and two more to go," she said.
Still in the hunt is first round co-leader Wie, though she couldn't keep pace with Park and Feng, firing a 67 to sit alone in third at 10 under.
"I was a little bit slow today and just didn't get the ball close to the hole on my second shot," said Wie, who added that she had to grind her way through the day. "I still can't complain. I'm still in contention."
The biggest climber of the day was Anna Nordqvist, who shot a 64 to jump into fourth place at 9 under, leapfrogging over LPGA rookie Xi Yu Lin, who shot 67 for the second straight day to head into the weekend at 8 under.
"I got off to a really good start and I hit it good all day. I think I hit all fairways and all greens, so that makes it a little bit easier," Nordqvist said. "I'm a little bit disappointed with the last couple holes, because I hit a lot of good putts that didn't go in. Overall, I'm happy and it was a good round."
The leaderboard is tight after Nordqvist, as the South Korean trio of Inbee Park, So Yeon Ryu and Na Yeon Choi, along with Spain's Belen Mozo, are tied for sixth at 7 under. Park had a 66 on the day, while the other three shot 67.
Six players are tied for 10th while five Canadian made the cut of 1-over 72 to advance to the weekend.
Jennifer Kirby, from Paris, Ont., and Langley, B.C.'s Sue Kim both shot 70 on Friday, and Brooke Henderson of Smiths Falls, Ont., came in at 71 to finish at 1 under after two rounds. Hamilton's Alena Sharp also snuck into the weekend by finishing off at even par after shooting 2 under.
Nicole Vandermade of Brantford, Ont., also survived with a 68 to finish on the line at 1 over.
Despite making the cut, Kirby was disappointed with her play on the day.
"It was a grind," said Kirby, who earned her LPGA card in December. "A little bit of good, a little bit of bad. I had a double (bogey) early on after a quick birdie, so that kind of put me back in line. I just tried to stay really patient and make some birdies."
Kirby's aim for the weekend is simple.
"Just stick to the game plan, just try and make more birdies really and eliminate some mistakes."
Maude-Aimee Leblanc of Sherbrooke, Que., (70) missed the cut at 2-over par, while Erica Rivard of Tecumseh, Ont., (73) finished at 4 over, Charlottetown's Lori Kane (77) at 8 over and Toronto's Rebecca Lee-Bentham (78) at 11 over also won't play on the weekend.