Thawed beef roast left in sink overnight is it safe has no smell?

It's not safe.

Refrigerators generally have a temperature range of 40°F (4°C) or below. When food goes above 40°F (4°C), bacteria will quickly begin to grow. When food hits the danger zone of 40°F to 140°F (4°C to 60°C) bacteria can grow rapidly multiplying in number and potentially producing harmful toxins.

According to the USDA, food left out in room temperature for over 2 hours may begin to grow harmful bacteria. It is highly recommended to always refrigerate or freeze thawed beef roast immediately to maintain food safety.