The South Korean scored six goals in a series of outstanding performances for the Red Devils prior to his departure for the Asian Cup in December.
Unfortunately for Park, when he returned to England just over a month later, he immediately suffered a hamstring injury that kept him out for another six weeks.
Walk in the Park: Ji-sung Park has returned to help United's title-charge
Saturday's win at West Ham heralded his return and the 30-year-old retained his place for Wednesday's Champions League win at Chelsea, where Park performed well before tiring in the latter stages. Now he wants to make the most of any further opportunities that come his way.
'It was frustrating to be injured just after coming back from the Asian Cup,' he said. 'The tournament wasn't great for me anyway so I was determined to come back and do well for United. Thankfully, I am back now but I realise I must play as well as I was doing before Christmas. I have confidence to do that.
Pure delight: The South Korean has always been a scorer of important goals for United
'I have been six years at United and before Christmas I was putting in some of my best performances of my entire time at Old Trafford. I want to reach that level again.'
With another tussle against Chelsea looming on Tuesday, it would be no surprise if Park was taken out of the firing line for tomorrow afternoon's encounter with Fulham.
A large number of changes are anticipated, with Rafael likely to be ruled out with a knee injury that forced him off at Stamford Bridge and Wayne Rooney missing through suspension.
There is some good news though as Anderson made a 45-minute appearance for the reserves last night and Darren Fletcher is due to return to training after being sidelined for almost a month by a chronic virus.
With a seven-point lead at the top of the Premier League to protect, United will not take Fulham lightly.
But who could blame them if they kept half an eye on Chelsea with the prospect of a Champions League semi-final against Inter Milan or Schalke so tantalisingly close.
'At Old Trafford we are not afraid of anyone,' said Park of Tuesday's decider. 'We believe in ourselves against Chelsea as well.'
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