The move was made Tuesday with an injury designation. That means if Kafka is not claimed by another team, the Vikings can either place him on injured reserve for the season or reach an agreement on an injury settlement.
Kafka was a fourth-round draft pick out of Northwestern by Philadelphia in 2010, playing in four games there in 2011 and spending last season with Tampa Bay.
The Vikings are set with Teddy Bridgewater as the starter and Shaun Hill as the backup. That leaves undrafted rookie Taylor Heinicke, who'll play the majority of the preseason finale Thursday at Tennessee. The Vikings have not committed to keeping three quarterbacks on the active 53-man roster, which must be set by Saturday.
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