Vikings wide receiver Percy Harvin returned to practice with his teammates on Friday. Harvin got into a heated argument with coach Brad Childress when Childress questioned Harvin's effort in practice, according to sources. Harvin, who hurt his ankle last Sunday at New England, is listed as questionable for Sunday against Arizona, but it's expected he will try to play. "He's a tough guy," Childress said. "Let's face it, he injured that foot on his first catch of the game [last Sunday in New England] and still was very productive. I would just say he's tough."