We document opportunistic behavior of financially constrained firms in the oil and gas production sector. Our results show that firms exposed to credit shocks engage in infill drilling, a controversial drilling practice that allows firms to enhance reported reserves and project larger production volumes, but carries a risk of a substantial damage to ultimate recovery. In contrast, our results do not indicate risk shifting showing that firms are not willing to take immediate risks. We also show that financing constraints prevent firms from timely adjusting drilling efforts in response to changing macroeconomic conditions. Our paper documents a previously unrecognized long term effect of credit supply shocks.