By FOX Sports staff
Arnold, who led the Mariners to the A-League crown last season after they beat Western Sydney Wanderers 2-0 in the Grand Final, had initially refused to commit to the club immediately after the triumph.
However, the uncertainty surrounding his future ended on Friday after the club announced on their official website that he had penned a new deal that will keep him at the Bluetongue Stadium until the end of the 2015/16 campaign.
Although Arnold admitted his "three-year plan" had concluded with last season's success, he revealed he had been motivated to stay on by new challenges that lay ahead.
"When I first came to the club we had a three-year plan that we wanted to implement," he said. "That three-year plan culminated in our Grand Final win last season, and the departure of an exciting batch of bright young players to overseas clubs.
"I am extremely proud of the boys we've developed and are now playing abroad.
"Now I am excited by the challenge to continue to be successful in the Hyundai A-League and AFC Champions League, while we groom more future Australian national team representatives."
A main reason behind Arnold's initial uncertainty over whether he was staying at the club stemmed from his desire to manage overseas, and he reveals that is something he still hopes to achieve in the future, although he insists he is happy to stay at Central Coast for now.
"I love this club and love living on the Coast," he added.
"However, at some point I do want to test myself abroad and implement what I have learnt throughout my coaching career at the highest level possible. But right now, there is no other club that offers me the chance to work in such a positive environment with a great group of players and staff.
"When I first came to the club we had 17 different training pitches in a season. Now we have our own training complex that is second to none in the competition; I truly believe there are exciting times ahead at the Mariners.
"I recently bought a property on the Coast so that should highlight how committed I am to continuing my work and being successful with the club."
Prior to taking over at the Mariners in 2010, Arnold had stints in charge of the Australia senior team, as well as the Under-23 side.