Incheon looked set to end their four-game winless streak as Park Tae-Min put the hosts 2-0 up in the 72nd minute, adding to Lee Chun-Soo's strike late in the first half.
But substitute Park Seong-Ho had other ideas and grabbed goals in the 77th and 90th minutes to keep Pohang a point clear at the summit of the Korean top flight.
Elsewhere in the Championship Round of the K-League, Jeonbuk Motors moved up to second place as they were held to a 0-0 draw by Suwon Bluewings at the Jeonju World Cup Stadium.
Choi Kang-Hee's side have a one-point lead over third-placed Ulsan but have now played two games more.
At the bottom of the Relegation Round there was more misery for rock-bottom Daejeon Citizen as they slumped to a 2-1 defeat to Gangwon.
Daejeon took the lead on the half-hour mark as Dong-Hyun Lee struck, but Bong-Jin Kim cancelled out that advantage prior to the break before Chun Jae-Ho's second-half double sealed the points for the visitors.
Gangwon are now four points clear of Daejeon, but are still two points short of escaping automatic relegation.
There was another K-League comeback at the Haman Stadium over the weekend as Seongnam beat Gyeongnam 2-1 away from home.
A Yun Young-Sun own-goal handed the hosts a 1-0 lead but Kim Tae-Hwan equalised with 20 minutes remaining before Server Djeparov netted a penalty two minutes from time to win it.
And in the weekend's final match, Jeju United won their third straight game as they earned a 1-0 victory against Chunnam Dragons.
