China's Yin Ruoning and Thailand's Atthaya Thitikul birdied five of the last seven holes to grab a share of the lead after Thursday's opening round of the LPGA Great Lakes Bay Invitational.Yin and Atthaya birdied the par-3 seventh and began the back nine with a birdie before reeling off their sizzling finish despite their lone bogey at the 15th.