The Brazilians are looking to make up from their exit from the CAF Champions League at the second qualifying round, with victory against Golden Arrows in the League Cup.
They already have the MTN8 cup in their trophy cabinet, having seen off Orlando Pirates in the 2026/27 final and are top of the Betway Premiership after 10 games.
Downs, meanwhile, beat Marumo Gallants 1-0 in the last 16 and are up against an Arrows side that saw off Chippa United 4-0.
Heading into the tie, the Tshwane side defeated Durban City 4-1 in the league as Arrows lost 1-0 to AmaZulu.
Speaking in the build-up to the game, Rayners admits that Sundowns won't have it easy against Mandla Ncikazi's Arrows.
"Knockout games are always difficult to play because you don't know what to expect from the other teams but as a team, we know how to win games like this, especially when it becomes difficult," Rayners said on IOL.
"We always have a lot of opportunities against them, but we just have to make sure we punish them as early as possible because once we do that, the game will open up and we know we'll win."
"I think their coach is a good coach especially when teams play against Sundowns, they know how to setup but we just need to do our job and work as hard as possible to win the game and get the result," added the Bafana Bafana attacker.
Rushine De Reuck has reflected on his time at Mamelodi Sundowns after scoring for Simba SC in their 3-2 Tanzanian Premier League comeback win over Namungo on Monday.
Former Mamelodi Sundowns and Kaizer Chiefs striker Leonardo Castro will bring his career to an end at Greenville Triumph, a club partly owned by Ronaldinho, according to reports.
Mamelodi Sundowns coach Miguel Cardoso will be looking to get more out of his attacking department with Brayan Leon and Iqraam Rayners expected to rediscover their scoring touch.
Mamelodi Sundowns coach Miguel Cardoso has questioned the consistency of refereeing in the Betway Premiership, suggesting that controversial decisions could once again influence the outcome of the title race.
