* For Vikings rookie QB J.J. McCarthy, the team's summer break won't be a vacation Star Tribune
* Kevin O'Connell wants 'competitive environment' for Vikings QBs Sam Darnold, J.J. McCarthy at training camp NFL.com
* Vikings Head Coach Names Starting Quarterback Heading Into Training Camp Newsweek
* Sam Darnold, not J.J. McCarthy, will open training camp as the Vikings' starting quarterback Yahoo Sports
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