Two home victories over Newcastle and West Ham and a draw at Fulham represents the minimum required by manager Sir Alex Ferguson.
United are third in the Premier League table, two points behind defending champions Chelsea who are the only team to still have a 100 per cent record.
But Park knows there is plenty of football to be played and United's form will get better.
"We're pleased to have won two of our three games, but we know we can still improve," Park told ManUtd.kr.
"We are experienced enough to know that as we get more games under our belt, our qualities will shine through.
"It has been a good start for Chelsea but we are not worried about that as it is a very long season.
"Each team has their ups and downs and the real test for Chelsea will come when things are not going so well for them."