The Cowboys struck first with a 34 yard field goal by David Buehler, but this 3-0 advantage would be their only advantage in the first half.
The Jags extended their lead in the second quarter. After a Jon Kitna interception gave Jacksonville the ball at their own 23 yard line, they needed just four plays to punch it in, on a 42 yard touchdown pass from Garrard to Marcedes Lewis.
Dallas drove to the Jacksonville one yard line toward the end of the half, but after opting to go for it on fourth down, came away with no points.
The Jaguars lead the Cowboys at half, 14-3.
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