Scheepers won the match 2-6, 6-2, 6-2 in one hour thirty-nine minutes.
Simmonds said she had started well and found it hard to believe she had won the opening set 6-2 in less than 30 minutes.
“I played so well in that opening set,” Simmonds said.
“The two very long games in the second set which I lost changed the momentum and gave Chani the confidence to split sets and run away as the winner.”
It was a crunch match for Scheepers, who has battled with injury this year, while 21-year-old Simmonds had nothing to lose.
Simmonds said she had impressed herself at the tournament, especially in the qualifying rounds.
“I played a very good match in the opening round of qualifying, a tight match where I won important points,” Simmonds said.
“Going into my second round qualies, I felt confident and was pleased with the way I played and won the match.
“In the final round qualies, I played what was probably the biggest ‘grind’ match of my life. I had to fight back from 1-4 down in the decider against Taylor to win and qualify, so that felt real good.”
Meanwhile Scheepers was pleased to have won the match.
“It was a big opening match,” Scheepers said.
“When I saw we had drawn each other I knew it was going to be a crunch match.
“Chanel is playing some great ball and got to the final of the Soweto Open on the hard courts which she likes, so for me, it was a good win, especially coming back from a shaky and nervous start.”
Scheepers will play against former world number one, Caroline Wozniacki of Denmark, in the second round of the tournament.