Gary Horton of Scouts Inc. ranked the NFL's top 10 most dynamic duos last week.

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Based on his rankings, the Cowboys will face seven of these pairings in 2012.

Here's what Horton said of his criteria: "The key to a truly impressive tandem is a twosome that works better together than they do apart. They cover each others weaknesses and enhance each others strengths -- even if their link isn't readily apparent."

There is one duo that Cowboys' opponents should worry about: Tony Romo and Jason Witten.

Romo has thrown 21 touchdown passes to Witten, tied for second-most in his career behind only Terrell Owens (34). Eight of these touchdown throws have given the Cowboys a lead in a game.

The interesting thing about Romo and Witten is they have good chemistry. Romo seems to always know where Witten is on the field whether he's the first, second or third read.

Reliability is important for a quarterback, and Romo can depend on Witten to make plays for him in the passing game. While the Cowboys don't have a true third receiver, Witten is literally that.

His athletic ability is underrated. Witten makes it hard for linebackers and safeties to cover him, and it seems he always finds open spots on the field to get open to make plays. Witten is always a tough receiver to bring down -- he finished tied for second with DeMarco Murray on the team with four broken tackles.

When he does that, it gives Romo comfort that he can get him the ball. Last season, Romo threw 142 passes to tight ends, sixth-most in the league.

This is the dynamic duo that opponents must be aware of when facing the Cowboys.