Baker inadvertently turned the ball into his own net when trying to clear his lines, handing Reading the lead in a crucial relegation battle.
However, the mistake did not prove too costly as Villa went on to win the match 2-1.
Far from being angry, Lambert was delighted with the way Baker responded to the own goal and praised his contribution to the side over the last few weeks.
"I though Nathan Baker was exceptional. He has been for the past number of weeks since I've put him at left back," said Lambert.
"It was important his head never went down which it didn't. Being young the slight thing in my head was how he reacted. I've got to give him so much credit."
The win lifted Villa out of the relegation zone, while Reading remain four points from safety in 19th.