zhuhai to Guangzhou, return to Guangzhou

Wish to make a day trip to Guangzhou while visiting Macau for 3 days. I shall take the less busy border crossing towards Zhuhai train station to go to Guangzhou south train station...Then after 1-day tour of Guangzhou, will take late evening train back to Zhuhai to Macao. Is it possibl to get train ticket on the day I reach the train station. I may consider spending 1 nite in Guangzhou. I am frm Malaysia