To soil with mud
Thunder rumbled again and a cold drop of rain gnawed at the mud on her cheek.
Then I slipped trying to rub mud on my pants to cover it up.
His shoes were covered with mud; he had torn his coat on the thorny tree.
At one point he splashed through a mud puddle, throwing mud and water all over her.
Five minutes later Ilyin, splashing through the mud, came running back to the shanty.