Juan Martin Del Potro Photos: Picture Gallery of Strokes

The position of his hips and the twisting of his upper body indicate that Juan Martin is hitting this forehand in a semi-open stance, which gives him a fairly even mix of rotational and linear power production. Del Potro's height may largely explain why his grip is closer to Eastern than to the more common (among the pros) Semi-Western. The main advantage of more western grips is to handle higher balls, but when you're as tall as Juan Martin, fewer balls seem high to you and more balls seem low, where a more western position is weaker.