Sunday's strike means that Aduriz is now La Liga's top scorer of headed goals since the start of the 2003/04 season with 48 to Ronaldo's 47.
The evergreen front man once again came to his side's rescue on Sunday, scoring a vital goal to earn his side a point at the San Mames.
The Spanish international rose like a salmon in the 76th minute to nod home a much-needed equaliser, but the goal was also significant in other ways.
Aduriz has now overtaken Ronaldo for headed goals scored in La Liga, something that the Portuguese will be keen to remedy at his earliest convenience.
That goal was Aduriz's seventh of the campaign so far and put an end to a frustrating run of four games without a goal.