The most significant deceptions in the play relate to Troy's self-deceptions. Troy chooses to believe that race kept him out of big league baseball, but the fact is age had at least as much to do with his failure to play major league baseball as race.
The fifteen years that Troy spent in prison made him too old for the major leagues. Troy ignores this argument, since to acknowledge that he was too old is to accept partial responsibility for not being able to play...
Similarly, Troy is convinced that race is keeping him from a promotion at work. He agitates for a promotion to the position of driver and succeeds. Troy may have been right about the biased practices of his work place, but he does not know how to drive. He has no license.
Once again, he has used the story of prejudice to justify (or cover for) his own deceit. Troy has a difficult time accepting blame and responsibility for wrong-doing, even while he fixates on his failures. He tends to blame others despite his own faults and flaws, which we see again in his affair.
Troy admits to his affair but cannot bring himself to apologize for it. Instead, he seeks to justify the affair and to blame his wife. (The affair is another example of deception. It was a secret for quite some time.)
Another example of deception is found in Cory's decision to continue to play football, for a time, against his father's clearly stated wishes. Cory lies and continues to attend practices.