"I have high expectations going into every week", Johnson said when asked about the U.S. Open.
Johnson will hardly be intimidated by the little-known Putnam, the only legitimate threat if he plays half decently.
Sunday's victory was the 18th PGA Tour win of Johnson's career, and his first since a triumph at the Sentry Tournament of Champions in Hawaii in January. The best U.S. Open finish by a victor of the St. Jude in the same year was a tie for third by Fred Couples in 1993, when the event was conducted two weeks before the Open.
Dustin Johnson is the hot favourite for the US Open after he emphatically reclaimed the world No.1 ranking.
He is bidding to win the season's second major for a second time after claiming the title at Oakmont in 2016.
Holding a four-stroke lead over second-place finisher Adam Putnam, all Johnson had to do on the 18th hole was avoid catastrophe on a historical level. After bogeys at 12 and 13 he bounced back with birdies at 14 and 16. "I just need to go out there and have a good mind-set and just get ready for the weekend for the final couple of groups". I know if I can drive it in the fairway that I'm going to give myself a good look for birdie.
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She said the global community was at the beginning of a very long process: "The detail is still to be worked through". So you never know. "So talking about withdrawal of U.S. forces is something that needs to be really thought through".
At the 445-yard par-4 sixth, Bryan got on in 2 and missed his par putt from 4 feet, finishing with a 3-putt bogey.
Johnson had already shown off his ludicrous velocity earlier in the day by hitting a 307-yard drive with an iron on the hard par-4 10th hole.
Putnam, meanwhile, who has yet to win on the PGA Tour, said he would take positives from the way he managed to steady his round after dropping three shots in his opening five holes.
"It obviously went pretty well", said Snedeker, the 2012 FedExCup champ. John Daly withdrew before the second round.
Johnson shot 7-under 63 for his lowest round this year and grabbed a one-stroke lead Friday after 36 holes at the St. Jude Classic.
He had made three birdies and just one bogey as he stepped on to the final hole and in characteristically nonchalant fashion he proceeded to hole his second from 170 yards.