The Brazilian scored the only goal to keep his side at the top at the expense of Braga, but he foresees a tough fight to secure the championship ahead of Benfica
The powerful forward made the difference on Saturday evening, scoring the only strike of the match to help the Dragao overcome the third-placed side 1-0 at home.
The win effectively ends Braga's chances of lifting the title, as they sit five points behind the leaders with just four games left.
Closest title rivals Benfica, meanwhile, play on Sunday in a Lisbon derby against Sporting and are currently four points behind Porto with a game in hand.
But speaking after the game, Hulk was adamant that his team-mates would not be complacent as they enter the final straight of the season, and pointed out that anything could still happen.
"We knew that we were taking on one of the strongest sides in Portugal, but we managed the victory. Nothing has been decided yet, there are still four games to play," he explained to reporters.
"We will try and stay humble, we have only picked up three points, albeit important ones."
Saturday's goal marked Hulk's 15th in the 2011-12 season, a total that represents fewer than half of the 36 he scored in all competitions the year before.
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