MINNEAPOLIS -- San Antonio Spurs guard Stephon Castle is one of the league's best defenders, often tasked with checking the other team's best player. For the Minnesota Timberwolves, that would be Anthony Edwards. While Castle has spent plenty of time harassing him in the first four games of the series he's spent a little more time on a less likely assignment. According to the NBA's matchup tracking data , the Wolf that San Antonio's second-year star has bothered the most is veteran big man Julius Randle. "He's very physical, it's a tough matchup," Castle said in the locker room after Game 4 . "He's more of a four, you know, a bigger player. So he uses his body a lot." It might sound crazy to guard an ox of a forward/center with a point guard. The truly crazy part, though, is that it's working out pretty well for the smaller player. The data shows that Castle has spent more time on Randle than on any opponent this playoff run other than Deni Avdija.…