Tha Chatchai Police were called to the scene, about 500 metres south of the Phuket Checkpoint, at 1am.
Officers arrived with Kusoldharm Foundation and Mai Khao rescue workers to find 23-year-old Trongjit Kongbangpor, from Songkhla, pinned under the cab of the six-wheeled Bangkok-registered Isuzu truck, which had flipped onto its side beside the road.
Ms Trongjit had suffered a serious injury to her left arm. Rescue workers took an hour to cut her free from the wreck and transported her to Thalang Hospital.
Ms Trongjit’s boyfriend, 27-year-old Suchinda Yamloi, also from Songkhla, told police that he was delivering goods bound for 7-Eleven stores in Patong.
Mr Suchinda, a driver for Dynamic Co Ltd, said he had picked up his load of produce from a 7-Eleven depot in Surat Thani at 9pm last night and was en route to Patong when the accident happened.
He told police that he was driving in the right lane southbound when a pickup truck behind him started driving erratically, wanting to pass him.
Mr Suchinda moved the truck into the left lane so that the pickup could pass, but the front-left wheel went off the road. The truck hit a sign and onto its side, he told police.
Police have yet to confirm whether Mr Suchinda will face any charges for the accident.
Thalang Hospital has reported that Ms Trongjit is safe, but declined to confirm any other details of her condition.