Teekay Tankers saw rates fall to four-year lows in the second quarter as vessel oversupply hit at a time of weaker shipping demand. The third quarter will be weaker still, but 2018 is setting up for a recovery.

Chief executive Kevin Mackay says the weak tanker cycle provides even more justification for its pending merger with Tanker Investments Ltd.

The deal is "consistent with our strategy of increasing shareholder value throughout the tanker cycle," Mackay told analysts.