Damien Duff was replaced as Andy Keogh came off the bench at half-time and his second half goal got the draw after the home side had taken an early lead in the Algarve.
Trapattoni said
"It was good opportunity to see the players in action. At this stage, after just a few days together, the players are still thinking about things rather than playing instinctively. Their mentality is good but there is still work to be done to change some of their habits.
"The pitch was not good and some of the passes which normally would have been accurate were not. I didn't expect any more today because we were missing six senior players."