A former high-ranking Enron Corp. trading and retail energy executive delivered the most bruising punches so far to company founder Kenneth Lay and former Chief Executive Jeffrey Skilling Tuesday in the fifth week of their fraud and conspiracy trial, saying it was standard to “play fast and loose with our rules” when it came to earnings manipulation.

David Delainey, who impressed his superiors enough to be chosen to run the profitable wholesale trading franchise until early 2001 when he took the helm of a highly touted retail energy unit, Enron Energy Services, told jurors he reluctantly acquiesced to a Skilling-approved plan to move the retail unit’s trading arm into the larger trading franchise to hide $200 million in losses.