Sundowns roped in the services of Pieterse from SuperSport United before letting go of Ghanaian shot-stopper Razak Brimah in the current transfer window.
The Bafana Bafana international joins Onyango and Kennedy Mweene – both of whom are long-serving number ones at their respective national teams, as well as Thela Ngobeni in the running for the sole spot between the sticks for The Brazilians.
The former CAF African-based Player of the Year has no concerns over the signing and, in fact, believes the arrival of the ex-Kaizer Chiefs keeper benefits himself and the club as a whole.
“Competition is always good, it improves you as a person and a player, and I need to continue fighting for my position as a goalkeeper, because any of them can play and the team can win,” Onyango tells KickOff.com.
“It’s a healthy competition, we have a lot of games to play this season and, for me, I welcome every challenge and I’ll fight. When given a chance, I have to make sure I give my best.”
The Ugandan international has been an ever-present in coach Pitso Mosimane’s side, averaging over 30 appearances per season, for the last three years, during which he has won two Absa Premiership titles as well as the CAF Champions League and Super Cup.
However, the 33-year-old still feels he can learn a thing or two from 26-year-old Pieterse, who played mostly as second-choice behind Ronwen Williams at Matsatsantsa.
“We learn from each other, learning never stops. He’s also got experience of playing in Africa, he played [as a reserve] with SuperSport until they reached the [2017 Confederation Cup] final,” he adds.
“So, I will learn a few things from him and he will learn a few things from me, which is good and keeps the team, especially the goalkeeping department, going.”