Angel Yin rammed in a 30-foot par putt on her opening hole, setting the tone for a day of big putts and 3-under 69 that gave her a two-shot lead Friday in the CME Group Tour Championship and the chase for the $4 million prize. Very clear in her rearview mirror was Nelly Korda. Korda, coming off her seventh win of the season last week, opened with a 72 and was eight shots behind.