The J-League Manager of the Year indicated that changes would be made to his squad as they look to defend their title and compete for the right to return to the Club World Cup
The J-League champions gave away an early lead when Hiroki Mizumoto put through his own net, but they drew level through Satoru Yamagishi's strike and won in the second half through captain Hisato Sato's double.
Before the match, both manager Moriyasu and his players had stressed the importance of playing against Asian competition ahead of their 2013 ACL campaign.
"Ulsan attack from the back with long balls," Moriyasu said after the game. "That's what we expected, so we played compactly and defended together.
"The first goal we conceded was an unfortunate own goal, but the second goal was not well-defended and that's what I told my players.
"We want to do well in next year's ACL. We will play Korean teams, so it is good we played Ulsan today.
"But then again, our team might be different next season, so we'll need to reconfigure and improve our roster before the ACL or it will be difficult.
"We might have finished only fifth [in the CWC], but we have the confirmation that Sanfrecce's own brand of football works at international level as well."
Meanwhile, defeated manager Kim Ho-Gon rued his players' failure to take their chances but admitted that the Japanese champions' tactical set-up paid dividends.
"We wanted to win for our fans, but we weren't aggressive enough," the Ulsan boss said at a press conference. "If we would have attacked more, it might have exposed us.
"Sanfrecce's organisation and balance are very good. They counterattack quickly and we were prepared for that, but they were very good today. It is easy to see why they won the J-League championship.
Kim also noted that several of his players, including Asian Player of the Year Lee Keun-Ho, were playing their last match for the club before beginning their mandatory military service.
"The fact that some of my players are set for military duty did not have any impact on the mood of the team or on the game," he continued.
"Defending the country is a duty, and these players will feature in the [second division] military team before returning to top football [in two years].
"The other teams from all over the world are very strong. We hope to win the ACL again and come back to this international stage, to be even better."