Sudan are the first team with a squad made up entirely of players from clubs in their own country to reach the last eight since Tunisia in 1996.
"I'm happy with my players who have proven they can play at the highest level, because they all come from the Sudanese championship," he said from Bata, Equatorial Guinea, where Tuesday's 2-1 win over Burkina Faso allowed Sudan to advance on goal difference.
The win was also their first at the finals in 42 years, since they won their only Nations Cup title in 1970 at home in the final against Ghana.
National teams playing with domestic based players only is an anomaly in African football these days, given the mass migration of footballers from the continent, although Sudan also had an all home-based squad at their last Nations Cup appearance in 2008 when they lost all three matches without scoring.
Sudanese clubs, among the richest on the continent, have done consistently well in African club competition in recent years. Khartoum's Al Hilal, who have 10 players in the Sudan squad, were semi-finalists in last year's African Champions League.
Sudanese clubs import Brazilian players plus others from countries like Nigeria and Zambia and Abdallah said in an interview with Reuters the confidence from club achievements had rubbed off on the national team.
"There is also the advantage of being able to get them together much more frequently than other sides. I try to have a gathering at least weekly," said coach Abdallah, a former captain of the national team and university professor.
"I'm very pleased we are in the quarter-finals. We have made progress in every match after a defeat, a draw and finally now a victory. It was our best game against a very organised team. It was hard. We took full advantage of our opportunities and our defenders and our goalie concentrated hard in the game."
Sudan now meet Zambia in Bata on Saturday in the first of four weekend quarter-finals.
