The Great Danes, a point adrift of the relegation play-off spot, are yet to win a league game since their 2-1 win over Strasbourg on January 28.
And with three points separating both sides, the South Africa international believes that a win over the Unicorns could trigger a positive run, with eight games left in the current campaign.
“It will be a very important match for us, everyone knows that. We're 19th, Amiens are rivals in the relegation battle,” Mothiba told Ligue 1 website.
“So if we win, we give ourselves a bit of breathing space in the table, and we also take points off a direct rival. Against us will be a team that is solid at the back and quick up front. I have faith in us. We can win this match. We're going to win this match."
Sunday’s clash will reunite two former Mamelodi Sundowns players, Mothiba and Bongani Zungu - who will be part of a full-strength Amiens squad.
But the 22-year-old forward who has garnered two goals in six league appearances this season, is unfazed by the reunion as he reiterates his commitment to help Lille in their relegation battle.
"My team is Lille. That's my agenda, my work to give everything to the club. I want to do that. I won't hear talk of relegation," he continued.
“We're all determined to give 200% until the end of the season. Today, our focus is on Amiens and nothing else."
The game at the Stade Pierre-Mauroy will be played behind closed doors following the pitch invasion that marred Lille's encounter with Montpellier on March 10.