Darius Leonard's impressive start to his rookie campaign for the Indianapolis Colts earned another NFL award.

The linebacker out of South Carolina State, nicknamed "Maniac," is now the league's Defensive Rookie of the Month for September. A second-round pick, Leonard amassed 54 tackles through four games. It's the most any player's tallied through such a stretch for any team since at least 1994. Leonard also has seven tackles for loss and four sacks.

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His most memorable game so far was the Colts' Week 2 win against Washington in which he recorded 19 tackles, a sack and a forced fumble. That performance earned him the AFC Defensive Player of the Week nod.

Running back Joseph Addai was the last Colts player to earn a rookie of the month award for his November 2006 performance. Defensive end Dwight Freeney won it in back-to-back months in November and December 2002. Running back Dominic Rhodes won it for December 2001. And running back Edgerrin James won it in September and November 1999.