New Zealand's champions, fresh from winning the OFC Champions League, will face Bayern Munich, Benfica and Boca Juniors in Group C of the revamped tournament, which starts at various US venues on Saturday, and Posa acknowledged their uphill battle.
"It's quite possibly the toughest group we could have drawn," said Posa, who guided them to fifth place in the old Club World Cup in 2009.
"We have two traditional European powerhouses in Bayern Munich and Benfica, and Boca Juniors, who are also capable of going all the way.
"We have competed in many of the previous versions of the CWC competition, which has given us a broad range of experience allowing us to punch above our weight in the past. Our goals are to be prepared, and compete, to the best of our ability.''
Auckland enter the 32-team tournament months after claiming their 13th Oceania title and fourth in succession. Despite continental success, football remains a part-time commitment for the squad.
"All of the players have other jobs alongside their football commitments," Posa said. "However, they have an extraordinary dedication to their football outside of their working hours.
"Players have had to take annual leave from their jobs. Indeed, some of the players were unable to take time to attend both the OFC Champions League competition and the Club World Cup."
The mid-June to mid-July tournament timing means it falls during Auckland's season rather than after it, as the previous version of the competition did.
"The challenge of having the CWC fall in the middle of the season has been ensuring that players are in top form at the right times. However, I believe we're on track to achieve this," Posa said.
Serving as caretaker coach for Albert Riera, who's away for family reasons, Posa previously managed Auckland from 2008-10. In the 2009 Club World Cup, they defeated the UAE's Shabab Al Ahli and DR Congo's TP Mazembe to finish fifth.
The 63-year-old acknowledged how difficult it would be to repeat his 2009 success.
"It's nice to dream we could be that competitive again. However, we're realistic about the challenge," he said.
While temporary, Posa has maintained Auckland's established playing style.
"It has not been difficult to maintain a playing philosophy that has evolved at Auckland City over many years,'' he said.
"Of course, every coach puts their own fingerprint on a team.''
This stability underpins Auckland's continued success.
"This comes down to building on experience gained in previous competitions, and a consistent focus on being well-organised and prepared, both on and off the pitch," Posa said.
"The culture surrounding the team is such that they always want to win, and motivating them is no problem at all."
