He was transported by air to Mercy Hospital after being found unresponsive with an unknown medical issue at an El Reno home Thursday morning.
There, he simply could not make it through.
Box, who was sidelined with a back injury for the first half of the 2010 season and battled other injuries throughout his career, was a huge factor in solidifying the Sooner defense down the stretch that paved the way to an unprecedented seventh Big 12 Championship.
He recorded 37 tackles, including 2.5 tackles for loss, but perhaps his biggest play of the season was an interception in last year's Bedlam game.
With OU leading 30-24 halfway through the third quarter, Box anticipated OSU quarterback Brandon Weeden's read and picked him off, setting up OU for a crucial field goal.
Box had 107 tackles heading into his senior year.
Stay tuned and come on into Sooner Magic Insider as more news becomes available.
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