Uganda coach Milutin 'Micho' Sredojevic felt only one lapse in concentration handed Ghana a 1-0 win in their Africa Cup of Nations Group D opener.
Playing at their first finals in 39 years, Uganda acquitted themselves well overall but Micho admitted they were found wanting in a couple of areas.
"We paid for one mistake which is hard to explain," he said. This competition does not permit silly mistakes.
"We just lack a bit at the technical and tactical level."
Andre Ayew scored Ghana's goal from the penalty spot after defender Isaac Isinde had lost possession and pulled back Asamoah Gyan.
Uganda responded well after going a goal down and Serbian Micho saw enough to convince him they can still progress.
"We came here to show that we did not qualify by accident and no matter that we now have to face Egypt and Mali, we will give 200% to advance," he said.
In their last African Nations Cup appearance, Uganda lost to Ghana in the 1978 final.
The Cranes' next Group A game is in Port Gentil on Saturday against Egypt.
Source: BBC