Duckett has delivered in both the County Championship and NatWest T20 Blast of late.
He smashed a first innings 134 from 151 balls in a four-day game at Division Two leaders Lancashire last month before following it up with a second innings 88.
The 20-year-old has also excelled in the shortened form of the game, with vital displays against Yorkshire and Leicestershire, among others, helping the Steelbacks win six of their past eight games in the T20 Blast.
Ripley is delighted with the form of the talented youngster, who has stepped up to open the batting in the Championship and is at three in the Blast.
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He has helped make up for the loss of David Willey, who has been with England and is currently sidelined with an ankle injury.
And Ripley said: “In David’s absence, Ben has stepped up into that position (in the Blast) and he’s played very well.
“He did well at Yorkshire and he played very maturely on Sunday (in the nine-wicket win against Leicestershire), giving Richard (Levi) the strike and taking the boundaries when it was a good time to take the pressure off.
“You don’t want the game going into the last over and he put a spurt on there to make sure we got the job done before that.
“Ben’s been good and with his Championship form in opening the batting and scoring runs, it’s been a good month for him.”