Ghana made a losing start to their 2014 World Cup campaign after a 2-1 reverse to old foes USA in Natal on Monday in a Group G clash.
Client Dempsey opened the scoring with an early goal â€“under a minute- to set the tone for the Yankeesâ€™ revenge mission after suffering defeats in the last two meetings.
But Ghana were clearly the better with the chunk of ball possession but that was negated by the score line, a 1-0 deficit.
The Black Stars came to close to snatching the equalizer in the first half when captain Asamoah Gyan drilled a powerful shot just outside the box but it was palmed away by goalkeeper Tim Howard.
Just before the half-time whistle, a nice counter-attack on the right saw Christian Atsu break away and tee up Jordan Ayew inside the box but the Marseille striker mis-kicked from close range.
The Americans lost striker Jozy Altidore on 20 minutes when the Sunderland striker pulled a muscle chasing a ball.
In the second half, USA coach Jurgen Klinsmann was forced to make another substitute by replacing injured Matt Besler with John Brooks to grabbed the match winner.
But it was all about the Black Stars in this second stanza with Asamoah Gyan twice coming close but being repelled by either goalkeeper Howard or a deflection.
After prowling for the leveller, it finally came in the 82 minute when a nice back heel pass found Andre Ayew inside the box and the latter fired home with his left foot for the deserved goal.
When Ghana fans thought they were heading for a share of the spoils, USA stunned the 2010 quarter-finalists with a powerful header.
Brooks, who was left unmarked inside the box, connected home the match winner with four minutes to regulation time.
Ghana will next face leaders Germany, who thumped Portugal 4-0 in Salvador, Â on Friday in a must-win tie.