The Brazilians powered to a 3-1 victory at the Martyrs Stadium on Wednesday evening, with Anthony Laffor, Yannick Zakri and Sibusiso Vilakazi all on target.
The history between the two sides stems back to last year, when Vita beat Sundowns on aggregate in their preliminary round Champions League clash, but the Congolese side were disqualified after fielding an ineligible player in the earlier round.
However, 'Jingles' refused to boast after his side's first victory over the Black Dolphins away from home as he emphasised the importance of humility following a "difficult" win.
“In football it is always important to have humility after victory,” Mosimane said in the post-match press conference.
“To say that the match was easy would be arrogant. It was not easy, and remember that the score was 1-1 at half time. It was not easy.
“We just had more opportunities to score than them, but it definitely was not easy. We did our homework, as all coaches would do, even if we did our homework it still proved difficult."
Despite the two-goal margin at the end of 90 minutes, Mosimane felt his side were fortuitous to get their second half goals after mistakes by the Vita defence allowed them through, as he admitted respect for counterpart Florent Ibenge.
“The two goals we scored in the second half were the results of mistakes by their defence," he added. "We pressed them and stole the ball, saw opportunities and scored.
"I have great respect for my brother here, the Vita coach [Ibenge]. We played five in the midfield. Normally we play four, but we were more organised in defence and tried to put pressure to force them back.”
Sundowns are now joint leaders in Group C with Tunisian giants Esperance, whom they next host on Friday, June 2.