Related Clues:

• It's trying
• 'No ___, no gain'
• Grueling experience
• It might be in the neck
• ___ in the ass
• Test of one's mettle
• Difficult trial
• It can be chronic or shooting
• Suffering partner?
• Major inconvenience
• Some athletes play through it
• Clubber Lang's prediction for Rocky
• "Royal" nuisance
• It's no picnic
• T-___ (noted Auto-Tune user)