Park has admitted feeling the weight of home fans' expectations after slumping to two high-profile defeats in an arena that bears his name.
However, the local hero will face a severe test from China's Ning Zetao, who anchored China's 4x100 freestyle relay team to victory and won the 50m free earlier this week.
Ning, 21, was born with a bone infection in his knee that gives him excruciating pain when he trains his kicks. (Lonely Journey for Palestinian Swimmer)
"I was born with it and I can't complain about it," Ning told Chinese media recently. "The pain is too much when I train kicks. I am the slowest in kicks in my team."
He has also had a digestion problem which meant he could only eat soft food and could not complete a week of training for several years.
Japan's Kosuke Hagino also goes for his seventh medal of the Games in the men's 200m backstroke, where countryman Ryosuke Irie will start as slight favourite.
There is also the men's 50m butterfly and women's 800m freestyle to be decided among six swimming golds at stake Thursday.
With China pulling away in the medals table -- now 59 golds -- there are also 10 shooting, seven rowing, five gymnastics and three cycling golds, plus two titles each in fencing, weightlifting and triathlon and one for bowling.
- N. Korea seeks medal double -
Rim Jong-Sim and Kin Un-Ju will be looking to give North Korea their first weightlifting one-two in the women's 75kg class. China's world championships silver medallist Kang Yue will be looking to crash the Pyongyang party.
The seriously big boys enter the fray and the gold in the men's 94kg weight class looks like a two-horse race between Kazakhstan's Almas Uteshov and Liu Hao of China.
In the final day of velodrome action, all eyes will be on Hong Kong's Olympic medal-winner Sarah Lee Wai-sze.
She bagged one gold in the keirin and is looking for a second win in the individual sprint -- but will have to get past China's Lin Junhong in the semi-final.
Fastest qualifier Zhong Tianshi of China takes on Malaysia's Mustapa Fatehah Binti, who is proving a tough competitor in these Games.
The men will race in the keirin, with Malaysian riders Azizul Awang and Josiah Ng vying for gold.
In badminton, the men's singles early rounds see Chinese star Lin Dan take on Korean 18th seed Lee Dong-Keun in a re-run of the team singles match which Lin won in two games -- though the home side took gold overall.
Lee will be in jubilant mood after the Korean triumph but is unlikely to down Lin. World number one Lee Chong Wei of Malaysia will also step on court as he begins his final attempt to win an elusive Asian Games gold.
In football, Palestine will take on Japan and China play Thailand as the tournament reaches the second round stage.
The basketball groups continue with four men's matches and two women's.
In Group E, serious medal contenders, Iran and the Philippines, feature in the first heavyweight clash of the tournament at 0500 GMT. The winner will top the the group and should face an easier quarter-final opponent.
And in gymnastics, the focus will be on local hero and reigning Olympic champion Yang Hak-Seon as he takes on North Korea's Ri Se-Gwang in the vault.
Yang suffered a hamstring injury in training last week but recovered enough to compete in Wednesday's floor and rings, though he only managed seventh place in both events.