Kerley had to contend with six starts at a rowdy National Athletics centre before clocking 9.99sec for a comfortable second place behind heat winner Oblique Seville, the Jamaican winning in a personal best of 9.86.
"The first round was about taking it easy but I had to get through it after several false starts and I'm glad I held it together," said a relieved Kerley.
"You've just got to keep your emotions calm. You know you are ready to go, so you just have to control the feelings."
Seville said his performance had left him "very surprised".