Pakistani pacers Shoaib Akhtar [Images] and Mohammad Asif [Images] gave up their right to call for testing of 'B' samples while appearing before a drugs inquiry tribunal in Lahore [Images], a Pakistan Cricket Board official said on Friday.

The official said both players accepted the first test findings on their 'A' samples before the tribunal, but pleaded innocent to taking the substance knowingly to enhance their performances.

"They want the tribunal to sympathetically consider the fact that they had taken the banned substance accidentally and not on purpose before deciding on the penalties for them," the official said.

The tribunal, which includes barrister Shahid Hamid, Dr Waqar Ahmed of the Pakistan Sports Board and former Pakistan captain and coach Intikhab Alam, met at the Gaddafi stadium in Lahore for nearly five hours during which the players appeared before them twice.

"We recorded their detailed statements and heard out their arguments. Shoaib also brought his personal doctor, Dr Nauman Niaz, who pleaded his case on his behalf," Shahid Hamid said.

Shoaib and Asif had tested positive for the performance-enhancing steroid nandrolone prior to their opening match in the Champions Trophy against Sri Lanka [Images] and asked to return from India, where the tournament is being played.

The tests were conducted by the Pakistan Cricket Board.