They both opened with 6-under-par 66s after arriving on different paths of momentum.
Creamer's building on momentum, Pressel's changing hers.
Creamer, who's beginning to feel better after fighting a mysterious stomach ailment for six months, is coming off a tie for third at the Sybase Classic and a second-place finish the week before at the Salonpas Cup in Japan, the JLPGA's first major.
Before the Corning Classic began, Creamer was leading the tour in hitting greens in regulation by a substantial margin. She was at 79 percent compared to runner-up Wendy Ward's 74 percent. Creamer widened the margin on Thursday. She hit all 18 greens in regulation.
Pressel arrived this week having missed back-to-back cuts but thrived on the short course hitting 13 greens.