By FOX Sports staff
The A-League outfit looked on track to pick up a valuable three points at the Guiyang Olympic Sports Center, leading their Chinese opponents 1-0 courtesy of Mitchell Duke's 42nd-minute penalty.
However, Zlatan Muslimovic equalised for Guizhou with seven minutes remaining, before Qu Bo struck just two minutes later to complete a come-from-behind win for the hosts.
Despite the defeat, Arnold believes there was little between the sides but admitted the Mariners faded away in the final ten minutes.
"I don't think there is a big gap between two teams," he said on the AFC's official website. "We are almost at the same level for the first 80 minutes.
"It was our physical decline at the end that gave our opponents chances. Nevertheless, I don't think this game showed our full attacking abilities."
The result leaves Central Coast third in Group H, behind second place Guizhou on head-to-head record, and Arnold believes they are still in a good position to make the Round of 16 with two games left to go.
"I am still optimistic about our qualification possibilities," he added. "If we have all our main players together, we are quite strong.
"There is still a home game waiting for us and I think we will qualify."
Guizhou assistant coach Li Chun Man believes a combination of determination and a tactical masterstroke was key to Tuesday's result - their first win in their maiden Champions League campaign.
"It was a very tough but entertaining game," he said. "Our players didn't give up when we were behind in the first half.
"In the second half when more attacking was needed, we adjusted our tactics in time and finally won the game."
Buoyed at picking up the three points, Li is confident his side can go and qualify for the knockout round.
"This is our first AFC Champions League win, and besides that, the way we came back means a lot to us," he added.
"We are now feeling more confident for the two remaining games. I believe we can go further in the competition."
Prior to Tuesday's win, Guizhou had only picked up one point from three games after defeats to Kashiwa Reysol and Central Coast, and a 0-0 draw with Suwon Bluewings.