Morena carded a 4-under 41 at Ocean Club Golf Course at Atlantis Resort, which was truncated to 12 holes after being drenched with nearly a foot of rain Tuesday.
The Colombian finished the day at 9-under 81 through 24 of the scheduled 36 holes -- one stroke better than Lindsey Wright, who fired a 7-under 38 to move up 56 places into solo possession of second at minus-8.
Tied for third at 7-under 83 were Eun-Hee Ji (40) and Julieta Granada (42).
After a lengthy lightning delay Friday, 27 players completed their first rounds Saturday morning.
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