A slow start to 2024 has seen Ricciardo beaten on track in three out of four races so far by RB team-mate Yuki Tsunoda.
The only exception to that trend was the Bahrain Grand Prix, where team orders moved Tsunoda aside in the closing stages.
Expected to dominate Tsunoda this year after a handful of races together last season, pressure has been mounting on Ricciardo as he’s battled to match his team-mate.
However, Horner believes a single result will turn the 34-year-old’s season around.
“His team-mate is delivering and that naturally then puts pressure on you,” the Red Bull Racing boss said.
“But he’s been there before. I’m sure he’ll bounce back.”
Horner is a firm supporter of Ricciardo, offering the Australian a third driver deal following his early exit from McLaren.
The Red Bull Racing boss was also instrumental in promoting the eight-time race winner back into a race drive in place of Nyck de Vries last season.
In Australia, the Englishman spoke with Ricciardo on the grid prior to the race – despite the RB being well behind the two Red Bull Racing entries, which featured on pole and sixth.
Ricciardo was last on the grid in Melbourne after he exceeded track limits on his best lap in qualifying, and Zhou Guanyu started from the pit lane after a front wing change ahead of the race.
Meanwhile, Tsunoda qualified in the top 10 and finished a season-high seventh in the grand prix.
The Japanese driver was in the points again on home soil in Suzuka, while Ricciardo was an opening lap casualty following a clash with Alex Albon.
“Daniel’s a big boy, he’s, he’s been around, he’s been around the block. He knows how things work,” Horner ventured.
“And I think that he just needs to get good result in the bag, and then that smile will return.”
Ricciardo is one of seven drivers yet to score a point in 2024, Tsunoda having contributed all seven of RB’s constructors’ championship points.
The F1 season continues this weekend with the Chinese Grand Prix – an event Ricciardo won in 2018.