Related Clues:

• It's not light work
• Trudge through sludge
• Force one's way through mud
• Muddy trek
• Move through muck
• Walk heavily and firmly
• Work doggedly
• ''Double, double, ___ and trouble''
• Walk through the mud
• Tiring walk
• Unloved work
• March in mud
• Break one's back, so to speak
• Trudge, as through mud
• Tiring journey