Duvall tied the San Jose Giants' single-season record of 26 homers by going deep in his fifth consecutive game Wednesday night in a 14-12 loss to the Stockton Ports.
San Francisco's No. 15 prospect went 2-for-5 with a three-run blast -- his sixth homer of the week -- and four RBIs.
"I'm not surprised," San Jose manager Andy Skeels said of Duvall's performance. "But you never say that somebody is capable of coming to the ballpark and homering for a week straight unless their name is Barry Bonds or Albert Pujols. But this organization is very high on Adam, and we think he is capable of doing some great things.
"He has been a credit to our coaching staff and to hitting coach Gary Davenport and all of the people who have helped him along the way. But at the end of the day, the credit has to go to the player."
Duvall's deep shot to left field off Stockton starter Nate Long in the fourth inning moved him into a tie with Tim Flaherty, who had held sole possession of the franchise mark for more than a decade since setting it in 2001.
It also extended his California League home run lead and moved him into a tie for fourth in the Minors. Only Omaha's Wil Myers (33), Oklahoma City's Mike Hessman (29) and Frisco's Mike Olt (28) have more.
"Adam has been such a huge part of our ballclub," Skeels said. "With our recent success, he has been putting the team on his back and carrying us. It's not often you get to see a player perform this well. It's rare for a reason.
"It couldn't happen to a nicer guy or at a better time for us."
Selected by the San Francisco Giants in the 11th round of the 2010 Draft out of the University of Louisville, Duvall's homer came the first pitch of his first at-bat, a hanging breaking ball which he pulled to left field.
"He's not been missing too many of them," Skeels added. "He's been hitting everything. If it's been over the plate, he's been hitting it hard.
"He's been swinging the bat with a lot of confidence. Mechanically, he's very balanced and now he's a little bit taller in his stance than he was earlier. He's also swinging at better pitches. He does a lot of things classically well. He's short to the ball, he has nice lift, he's strong and he's quick through the zone. I'm confident his skills will translate at the Major League level."
Duvall has slugged 17 homers off right-handed pitchers and nine off southpaws. He's gone yard 16 times on the road and 10 times at Municipal Stadium. The Giants are 15-9 in games he's homered.
He's homered against all four other teams in the California League's North Division at least three times each, and he's also victimized Inland Empire five times despite only facing the South Division club 12 times.
The 23-year-old has gone yard in all nine innings. He's homered with nobody on base and no outs in an inning (three times), and he's gone yard with two on and two outs (twice). The only thing he hasn't done this year is hit a grand slam.
"He's a guy that hasn't been on people's radar screens, but he should be," Skeels said. "You just show up at the ballpark and see if he's going to do something special. Not only has he been putting up good numbers, but he's been clutch. That's a testament to the player he is."
Not to be overshadowed Wednesday night was Joe Panik, San Francisco's No. 5 prospect. He went 4-for-4, fell a triple shy of the cycle and extended his hitting streak to seven consecutive at-bats.
"Joe has been swinging the bat real well. It's been a nice tandem between Panik and Duvall," Skeels said. "Joe has been exhibiting all the things we know he can do. He's been driving the ball the other way and hitting the ball well to the pull side. He's been hitting with two strikes and he's been choosing good pitches.
"Any time somebody is swinging the bat well, it takes the pressure of the guys hitting around him. We have a nice 1-2-3 punch at the top of the order and we have had success with [Carter] Jurica, Panik and Duvall. He's like a pressure valve."