With the score at 1-1 and the goalkeeper at his mercy, the former Atletico Madrid youth star spurned a glorious opportunity to secure three points for the Porcupine Warriors in Kumasi.
On the end of an Emmanuel Gyamfi’s cross after Hearts failed to clear, the 27-year-old saw his languid shot from six yards roll wide, much to the dismay of the home fans.
"We dominated the game but a few mistakes we made resulted in the draw," Adams told footy-Ghana.
"At least I should have scored the last goal, so I take the blame for it but we will correct our mistakes and get better in the next game.
“Physically some of the players got tired but all the same, we fought throughout the 90 minutes and we got the equalizer after going down, so all the players deserve applause."
The result leaves Kotoko four points behind their arch-rivals on the league table.
Adams, who represented Ghana at the 2007 Fifa Under-17 World Cup in South Korea, joined Kotoko in May.