It has been confirmed that Daniel Ricciardo is to make a shock move to Renault next season. Horner has added his comments confirming he respects the Australian's decision to leave after a long-term relationship.
Speaking in a Red Bull statement he said: "We fully respect Daniel's decision to leave Aston Martin Red Bull Racing, and we wish him all the best in the future.
"We would like to thank him for his dedication and the role he has played since joining the team in 2014."
Ricciardo's time at Red Bull has resulted in seven race wins and 29 podiums. His most recent race win came at Monaco earlier this season. He also won the 2018 Chinese Grand Prix.
Horner's attention quickly turned to how they are going to replace the 29-year-old.
"We will now continue to evaluate the numerous options available to us before deciding on which drivers partners Max Verstappen for the 2019 season," Horner added.
"In the meantime, there are still nine races left in 2018 and we are fully focused on maximising every opportunity for Max and Daniel for the remainder of the season."
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