Related Clues:

• Run quickly
• Breed
• See 65-Across
• See 18-Across
• Humans, e.g.
• See 15-Down
• Go full tilt
• Kentucky Derby, e.g.
• Regatta, for example
• It may have four legs
• Tortoise-hare affair
• It's sometimes a drag
• Tour de France, for one
• Olympics event
• Marathon, e.g.